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Physics· 17 calculators

Popular
Physics · Physics
Acceleration Calculator
Free acceleration calculator — solve a = Δv/Δt and the four SUVAT kinematic equations for acceleration, final velocit...
physics↗
★ Editor's pick
Physics · Physics
Bernoulli Equation Calculator
Solve Bernoulli's principle for fluid pressure, velocity, and elevation. For incompressible, inviscid flow in pipes a...
physics↗
Physics · Physics
Density Calculator
Free density calculator — solve ρ = m / V for density, mass, or volume. SI units, worked examples, and reference tabl...
physics↗
Physics · Physics
E = mc² Calculator
Convert mass to energy or energy to mass using Einstein's equation E = mc². Results in joules, kilotons, or megatons ...
physics↗
Physics · Physics
G-Force Calculator
Calculate g-force from linear acceleration or circular motion. Uses standard gravity for accurate physics and enginee...
physics↗
Physics · Physics
Gravitational Force Calculator
Free gravitational force calculator — solve Newton's F = G·m₁·m₂/r² for force, mass, or distance. Worked Earth-Moon a...
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Physics · Physics
Kinetic Energy Calculator
Free kinetic energy calculator using KE = ½mv². Compute joules and momentum from mass and velocity, with worked car-c...
physics↗
Physics · Physics
Latent Heat Calculator
Calculate heat required for melting, freezing, vaporization, or condensation. Uses standard specific latent heat valu...
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Physics · Physics
Ohm's Law Calculator
Free Ohm's law calculator — solve for voltage, current, resistance, or power using V=IR and P=VI. Worked examples for...
physics↗
Physics · Physics
Photon Energy Calculator
Calculate photon energy from wavelength or frequency. Results in joules and electronvolts using exact Planck constant...
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Physics · Physics
Pressure Calculator
Free pressure calculator — solve P = F/A for pressure, force, or area, with instant kPa, bar, and psi conversions. Wo...
physics↗
Physics · Physics
Projectile Motion Calculator
Free projectile motion calculator — solve range, time of flight, max height and velocity components from initial spee...
physics↗
Physics · Physics
Terminal Velocity Calculator
Calculate terminal velocity for objects falling through air or other fluids using drag coefficient, mass, and fluid d...
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Physics · Physics
Thermal Expansion Calculator
Calculate linear thermal expansion for solids. Enter initial length, temperature change, and material coefficient to ...
physics↗
Physics · Physics
Torque Calculator
Calculate torque from force, lever arm, and angle. Supports Newton-metres, pound-feet, and dyne-centimetres with step...
physics↗
Physics · Physics
Wavelength & Frequency Calculator
Free wavelength calculator — convert between wavelength, frequency, and photon energy using c = λf and E = hf with ex...
physics↗
Physics · Physics
Speed of Sound Calculator
Calculate the speed of sound in air or helium from temperature using the exact physical formula c = √(γRT/M). Include...
physics↗
Genetics

Genetics· 11 calculators

Popular
Genetics · Genetics
Allele Frequency Calculator
Free allele frequency calculator — gene-count p and q from observed AA, Aa and aa counts. Autosomal or X-linked, with...
genetics↗
★ Editor's pick
Genetics · Genetics
Dihybrid Cross Calculator
Free dihybrid cross calculator. Enter two parent genotypes for two genes and get the 16-cell Punnett square, 9:3:3:1 ...
genetics↗
Genetics · Genetics
Hardy-Weinberg Equilibrium Calculator
Free Hardy-Weinberg calculator — enter one frequency and get p, q, p², 2pq and q². Shows the five assumptions and exp...
genetics↗
Genetics · Genetics
Punnett Square Calculator
Free Punnett square calculator for a one-gene cross. Enter two parent genotypes, pick complete, incomplete or codomin...
genetics↗
Genetics · Genetics
Blood Type Inheritance Calculator
Free blood type inheritance calculator. Enter both parents' ABO and RhD genotypes for exact child blood group probabi...
genetics↗
Genetics · Genetics
Carrier Probability Calculator
Free carrier probability calculator for autosomal recessive traits — combines both partners' evidence into an offspri...
genetics↗
Genetics · Genetics
Chi-Square Calculator for Genetic Ratios
Free genetics chi-square calculator — test observed counts against 3:1, 9:3:3:1, 1:2:1 or Hardy-Weinberg. Degrees of ...
genetics↗
Genetics · Genetics
Pedigree Probability Calculator
Free Bayesian pedigree probability calculator. Update a carrier risk using unaffected children already born, with the...
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Genetics · Genetics
Recombination Frequency Calculator
Free recombination frequency calculator — turn testcross offspring counts into map units, plus Kosambi and Haldane co...
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Genetics · Genetics
Sex-Linked Inheritance Calculator
Free X-linked inheritance calculator. Enter the mother's and father's genotypes and get affected and carrier probabil...
genetics↗
Genetics · Genetics
Trihybrid Cross Calculator
Free trihybrid cross calculator. Pick the phenotype you want at each of three genes and get its exact probability and...
genetics↗
Biology

Biology· 10 calculators

Popular
Biology · Biology
Bacterial Growth Calculator
Project a batch culture with lag, log and stationary phases. Solve for final density, time to a target OD, or the ino...
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★ Editor's pick
Biology · Biology
Cell Doubling Time Calculator
Find doubling time and specific growth rate from two OD600 or cell-count readings taken in log phase. Returns generat...
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Biology · Biology
Serial Dilution Calculator
Plan a serial dilution series: concentration in every tube, transfer and diluent volume per step, and the total dilut...
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Biology · Biology
CFU Calculator
Convert a plate count into CFU/mL, single plate or the ISO 7218 / FDA BAM weighted mean across two dilutions, with co...
biology↗
Biology · Biology
Cell Viability Calculator
Percent cell viability from trypan blue counts or from MTT/XTT absorbance, using the ISO 10993-5:2009 equation, plus ...
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Biology · Biology
Enzyme Activity Calculator
Convert an absorbance rate or a measured substrate amount into enzyme units, specific activity and SI katals, with th...
biology↗
Biology · Biology
Hemocytometer Calculator
Turn counting-chamber tallies into cells/mL. Works with any Neubauer, Fuchs-Rosenthal or custom grid — the ×10,000 fa...
biology↗
Biology · Biology
Log Reduction Calculator
Convert between log reduction, percent kill and surviving counts, with the 3-log, 4-log and 5-log levels named in US ...
biology↗
Biology · Biology
MOI Calculator
Work out virus volume, MOI or cell number from a titre, and see the Poisson split — at MOI 1, 36.8% of cells still re...
biology↗
Biology · Biology
OD600 to Cells Calculator
Convert OD600 to cells per mL with your own calibrated factor, or derive that factor from a counted sample. Flags rea...
biology↗
Wave Mechanics

Wave Mechanics· 28 calculators

Popular
Wave Mechanics · Wave Mechanics
Beat Frequency Calculator
Beat frequency calculator: f_beat = |f₁ − f₂|. Why two close tones pulse, and how musicians use beats to tune to with...
wave-mechanics↗
★ Editor's pick
Wave Mechanics · Wave Mechanics
Doppler Effect Calculator
Calculate observed frequency shift for moving sound sources and observers. Step-by-step acoustic Doppler effect with ...
wave-mechanics↗
Wave Mechanics · Wave Mechanics
Index of Refraction Calculator
Calculate absolute phase refractive index from the exact vacuum light speed and an entered phase velocity in the medi...
wave-mechanics↗
Wave Mechanics · Wave Mechanics
Wave Speed Calculator
Find wave speed with v = f × λ. Enter frequency and wavelength to get phase speed in m/s, with worked checks against ...
wave-mechanics↗
Wave Mechanics · Wave Mechanics
Acoustic Impedance Calculator
Calculate characteristic plane-wave acoustic impedance from medium density and longitudinal sound speed with explicit...
wave-mechanics↗
Wave Mechanics · Wave Mechanics
Compton Scattering Calculator
Calculate photon wavelength shift for scattering by a stationary free electron at a stated angle with explicit cohere...
wave-mechanics↗
Wave Mechanics · Wave Mechanics
Contact Lens Vertex Calculator
Vertex distance calculator: F₂ = F₁/(1 − dF₁) converts lens power between planes — why strong glasses and contact len...
wave-mechanics↗
Wave Mechanics · Wave Mechanics
Cutoff Frequency Calculator
RC cutoff frequency calculator: f_c = 1/(2πRC). Find the −3 dB corner of a low-pass or high-pass RC filter and the ro...
wave-mechanics↗
Wave Mechanics · Wave Mechanics
Diffraction Grating Calculator
Diffraction grating calculator: θ = asin(mλ/d) locates each bright order from wavelength, line spacing, and order, wi...
wave-mechanics↗
Wave Mechanics · Wave Mechanics
Hair Diffraction Calculator
Calculate hair-diameter estimate from laser wavelength, screen distance, and adjacent dark-fringe spacing in the smal...
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Wave Mechanics · Wave Mechanics
Harmonic Wave Equation Calculator
Calculate instantaneous transverse displacement for a one-dimensional sinusoidal traveling wave from explicit amplitu...
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Wave Mechanics · Wave Mechanics
Laser Beam Divergence Calculator
Calculate diffraction-limited Gaussian-beam far-field half-angle from wavelength and beam-waist radius with explicit ...
wave-mechanics↗
Wave Mechanics · Wave Mechanics
Laser Beam Expander Calculator
Calculate ideal afocal beam-expansion ratio and expanded collimated beam diameter from two focal-length magnitudes wi...
wave-mechanics↗
Wave Mechanics · Wave Mechanics
Laser Beam Spot Size Calculator
Calculate ideal Gaussian 1/e² beam radius after propagation from a waist using vacuum wavelength with explicit cohere...
wave-mechanics↗
Wave Mechanics · Wave Mechanics
Lensmaker's Equation Calculator
Calculate paraxial thin-lens focal length in air from refractive index and signed spherical surface radii with explic...
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Wave Mechanics · Wave Mechanics
Magnetic Declination Calculator
Calculate magnetic declination with a sourced formula, guarded inputs, a worked example, and clearly stated scope.
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Wave Mechanics · Wave Mechanics
Magnetic Permeability Calculator
Calculate magnetic permeability from magnetic flux density and magnetic field strength in coherent SI units with expl...
wave-mechanics↗
Wave Mechanics · Wave Mechanics
Mirror Equation Calculator
Calculate signed image distance for a spherical mirror from signed focal length and object distance under one explici...
wave-mechanics↗
Wave Mechanics · Wave Mechanics
Photon Detection Efficiency Calculator (SiPM)
Calculate measured photon-detection efficiency ratio from detected event count and incident photon count with explici...
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Wave Mechanics · Wave Mechanics
Solenoid Magnetic Field Calculator
Calculate ideal long-solenoid interior magnetic flux density from permeability, turns, current, and coil length with ...
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Wave Mechanics · Wave Mechanics
Sound Absorption Coefficient Calculator
Calculate energy absorption coefficient from absorbed and incident sound-energy magnitudes with explicit coherent-SI ...
wave-mechanics↗
Wave Mechanics · Wave Mechanics
Wavenumber Calculator
Convert wavelength to wavenumber both ways: angular k = 2π/λ in rad/m and spectroscopic 1/λ in m⁻¹, with the cm⁻¹ con...
wave-mechanics↗
Wave Mechanics · Wave Mechanics
Compton Wavelength Calculator
Calculate unreduced Compton wavelength from a particle rest mass using exact SI Planck-constant and light-speed defin...
wave-mechanics↗
Wave Mechanics · Wave Mechanics
Cyclotron Frequency Calculator
Calculate nonrelativistic cyclotron frequency magnitude from charge magnitude, magnetic flux density, and particle re...
wave-mechanics↗
Wave Mechanics · Wave Mechanics
De Broglie Wavelength Calculator
De Broglie wavelength calculator: λ = h/(mv). See why electrons diffract like waves while everyday objects never do, ...
wave-mechanics↗
Wave Mechanics · Wave Mechanics
Laser Brightness Calculator
Calculate average radiance-style brightness from optical power, emitting beam area, and solid angle under a stated un...
wave-mechanics↗
Wave Mechanics · Wave Mechanics
Laser Linewidth and Bandwidth Calculator
Calculate small-bandwidth frequency linewidth from centre wavelength and wavelength linewidth using the first-order c...
wave-mechanics↗
Wave Mechanics · Wave Mechanics
Two-Photon Absorption Calculator
Calculate intensity-dependent two-photon absorption coefficient contribution from a supplied β coefficient and optica...
wave-mechanics↗
Chemistry

Chemistry· 52 calculators

Popular
Chemistry · Chemistry
Boiling Point Elevation Calculator
Free boiling point elevation calculator. Solve ΔTb = i·Kb·b, size the solute for a target elevation, or derive Kb fro...
chemistry↗
★ Editor's pick
Chemistry · Chemistry
Combined Gas Law Calculator (Boyle, Charles & Gay-Lussac)
Solve P1V1/T1 = P2V2/T2 for any state variable. Covers Boyle's, Charles's and Gay-Lussac's laws — the calculator name...
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Chemistry · Chemistry
Dilution Calculator
Free dilution calculator (C1V1=C2V2). Solve for initial or final concentration, or initial or final volume — any cons...
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Chemistry · Chemistry
Electronegativity Calculator
Calculate absolute difference between two electronegativity values supplied on the same named scale with explicit coh...
chemistry↗
Chemistry · Chemistry
Empirical Formula Calculator
Turn percent composition or element masses into an empirical formula, and into the molecular formula when you know th...
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Chemistry · Chemistry
Equilibrium Constant Calculator
Calculate the equilibrium constant Kc from molar concentrations of reactants and products and their stoichiometric co...
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Chemistry · Chemistry
Freezing Point Depression Calculator
Free freezing point depression calculator. Solve ΔTf = i·Kf·b, find a solute's molar mass by cryoscopy, or derive Kf ...
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Chemistry · Chemistry
Ideal Gas Law Calculator
Free ideal gas law calculator — solve PV = nRT for pressure, volume, moles, or temperature. SI units, R = 8.314 J/(mo...
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Chemistry · Chemistry
Limiting Reagent Calculator
Find which of two reactants runs out first. Enter formulas, coefficients and masses to get the limiting reagent, theo...
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Chemistry · Chemistry
Molality Calculator
Free molality calculator — b = n/m. Solve mol/kg from solute mass and solvent mass, or convert mol/L to mol/kg using ...
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Chemistry · Chemistry
Molar Mass Calculator
Free molar mass calculator — enter a chemical formula like H2O, Ca(OH)2, or C6H12O6 and get g/mol from IUPAC 2021 ato...
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Chemistry · Chemistry
Molarity Calculator
Free molarity calculator — solve for molarity, moles, volume, mass, or dilution using M = n/V and C1V1 = C2V2. Worked...
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Chemistry · Chemistry
Mole Calculator
Convert grams to moles, moles to grams, or work back to molar mass. n = m / M with IUPAC CIAAW 2024 atomic weights an...
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Chemistry · Chemistry
Normality Calculator
Free normality calculator — N = z × M. Enter the equivalents per mole for your reaction to get eq/L, equivalent weigh...
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Chemistry · Chemistry
Percent Composition Calculator
Enter a chemical formula and get the mass percent of every element in it, plus the grams of any element in a sample o...
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Chemistry · Chemistry
Percent Yield Calculator
Free percent yield calculator: enter actual and theoretical yield, or solve for either one. Explains yields above 100...
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Chemistry · Chemistry
Solubility Product (Ksp) Calculator
Convert Ksp to molar solubility for any AxBy salt and back again, with ion concentrations, mg/L, and the USGS-sourced...
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Chemistry · Chemistry
Theoretical Yield Calculator
Convert a mass of limiting reactant into the maximum mass of product a balanced equation allows. Shows moles, mole ra...
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Chemistry · Chemistry
pH Buffer Calculator
Calculate buffer pH using the Henderson-Hasselbalch equation. Enter pKa and concentrations of weak acid and conjugate...
chemistry↗
Chemistry · Chemistry
pH Calculator
Free pH calculator — solve pH from [H+], [H+] from pH, pOH, and [OH-] with temperature-dependent Kw (CRC handbook). W...
chemistry↗
Chemistry · Chemistry
pKa Calculator
Convert Ka to pKa, pKa to Kb and pKb, recover a pKa from a measured buffer pH, and correct pKa for temperature using ...
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Chemistry · Chemistry
Acid-Base Titration Calculator
Find an unknown acid or base concentration from titration data. Enter titrant concentration, volume, and stoichiometr...
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Chemistry · Chemistry
Atom Economy Calculator
Calculate percentage atom economy from a balanced equation, using Trost's definition. Also gives by-product mass and ...
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Chemistry · Chemistry
Average Atomic Mass Calculator
Work out an element's average atomic mass from its isotope masses and natural abundances, with NIST nuclide data and ...
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Chemistry · Chemistry
Buffer Capacity Calculator
Compute Van Slyke buffer capacity β = dCb/dpH from pKa, buffer concentration and pH, with the water terms included an...
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Chemistry · Chemistry
Common Ion Effect Calculator
Find how far a common ion suppresses a salt's solubility. Enter log Ksp, stoichiometry and the ion already present; g...
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Chemistry · Chemistry
Electrolysis Calculator
Calculate theoretical deposited or consumed mass from current, time, molar mass, and electron stoichiometric number u...
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Chemistry · Chemistry
Electron Speed Calculator
Electron speed calculator: kinetic energy in eV to relativistic speed via γ = 1 + K/(mₑc²), v = c√(1 − 1/γ²) — exact ...
chemistry↗
Chemistry · Chemistry
Henry's Law Calculator (Gas Solubility)
Solve c = H·p for dissolved gas concentration, partial pressure or the Henry's law constant, in all four IUPAC conven...
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Chemistry · Chemistry
Mass Percent Calculator
Percent concentration of a solution on the USP w/w, w/v and v/v bases. Solve for the percentage, the solute to weigh,...
chemistry↗
Chemistry · Chemistry
Mole Fraction Calculator
Free mole fraction calculator — x = n/n_total for a binary mixture. Work from moles, masses or molality, and convert ...
chemistry↗
Chemistry · Chemistry
Moles to Atoms Calculator
Convert moles to atoms, molecules or ions with the exact SI Avogadro constant — and back again. Set the entities per ...
chemistry↗
Chemistry · Chemistry
Osmotic Pressure Calculator
Compute osmotic pressure from Π = i·c·R·T in kPa, bar and atm — or invert it for concentration, molar mass, or the me...
chemistry↗
Chemistry · Chemistry
PPM to Molarity Calculator
Free ppm to molarity calculator. Convert mass-basis ppm, mg/L and mol/L using molar mass and solution density — with ...
chemistry↗
Chemistry · Chemistry
Partial Pressure Calculator (Dalton's Law)
Calculate partial pressure from mole fraction, moles or total pressure using Dalton's law p = xP. Results in kPa, mmH...
chemistry↗
Chemistry · Chemistry
Percent Ionization Calculator
Exact percent ionization and pH of a weak acid or weak base, solved including water's autoionization — with the √(Ka/...
chemistry↗
Chemistry · Chemistry
Protein Molecular Weight Calculator
Protein molecular weight calculator: average residue masses plus one water give the neutral mass of any one-letter se...
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Chemistry · Chemistry
Raoult's Law Calculator (Vapour Pressure of Solutions)
Apply Raoult's law p = x·p* to find the vapour pressure above a solution, the vapour-pressure lowering, and the vapou...
chemistry↗
Chemistry · Chemistry
Reaction Time Calculator
Calculate reaction time with a sourced formula, guarded inputs, a worked example, and clearly stated scope.
chemistry↗
Chemistry · Chemistry
Root Mean Square Speed Calculator for Ideal Gas
Calculate ideal-gas molecular root-mean-square speed from absolute temperature and molar mass with explicit coherent-...
chemistry↗
Chemistry · Chemistry
Specific Gas Constant Calculator
Calculate mass-specific gas constant from the molar gas constant and a supplied molar mass with explicit coherent-SI ...
chemistry↗
Chemistry · Chemistry
Stoichiometry Ratio Calculator
Convert between any two species in a balanced equation via the mole ratio, in both directions: how much reagent you n...
chemistry↗
Chemistry · Chemistry
Titration Curve Point Calculator
Find the pH at any point of a monoprotic titration — start, buffer region, equivalence or beyond — from one exact cha...
chemistry↗
Chemistry · Chemistry
Volt to Electron Volt Calculator
Convert volts to electron volts: a particle of charge z through V volts gains E = zV eV. Covers ions, electrons, and ...
chemistry↗
Chemistry · Chemistry
van 't Hoff Equation Calculator
Use ln(K2/K1) = -(ΔH°/R)(1/T2 - 1/T1) to move an equilibrium constant between temperatures, or fit a reaction enthalp...
chemistry↗
Chemistry · Chemistry
Bleach Dilution Calculator (ppm Available Chlorine)
Work out how much bleach and how much water to mix for a target ppm of available chlorine, converting correctly betwe...
chemistry↗
Chemistry · Chemistry
Bond Order Calculator
Calculate molecular-orbital bond order from nonnegative bonding and antibonding electron counts with explicit coheren...
chemistry↗
Chemistry · Chemistry
Combustion Analysis Calculator
Enter sample mass with the CO2 and H2O collected and get carbon, hydrogen and oxygen masses plus the empirical formul...
chemistry↗
Chemistry · Chemistry
Double Bond Equivalent Calculator
Calculate degree of unsaturation from carbon, hydrogen, nitrogen, and halogen atom counts for a neutral closed-shell ...
chemistry↗
Chemistry · Chemistry
Excess Electrons Calculator
Calculate number-equivalent of excess elementary charges from a net charge magnitude using the exact SI elementary ch...
chemistry↗
Chemistry · Chemistry
Intrinsic Carrier Concentration Calculator
Intrinsic carrier concentration calculator: nᵢ = √(N_cN_v)·exp(−E_g/2k_BT). See how band gap and temperature set a pu...
chemistry↗
Chemistry · Chemistry
Reaction Quotient Calculator
Calculate dimensionless reaction quotient for a supplied aA+bB to cC+dD activity model with explicit coherent-SI inpu...
chemistry↗
Fluid Mechanics

Mechanics· 32 calculators

Popular
Mechanics · Mechanics
Centripetal Force Calculator
Calculate centripetal force from mass, velocity, and radius. Step-by-step physics tool with formulas, worked examples...
mechanics↗
★ Editor's pick
Mechanics · Mechanics
Force Calculator (F = ma)
Free force calculator — solve Newton's Second Law F = m·a for force, mass, or acceleration in SI units (newtons, kg, ...
mechanics↗
Mechanics · Mechanics
Free Fall Calculator
Calculate free fall time and impact velocity from height. Physics tool with step-by-step math, adjustable gravity, an...
mechanics↗
Mechanics · Mechanics
Friction Factor Calculator
Calculate Darcy friction factor for fully developed turbulent pipe flow using the explicit Haaland approximation with...
mechanics↗
Mechanics · Mechanics
Gravitational Potential Energy Calculator
Calculate gravitational potential energy using Newton's law U = -GMm/r and escape velocity. For orbital mechanics, as...
mechanics↗
Mechanics · Mechanics
Momentum Calculator
Free momentum calculator using p = mv. Solve for momentum, mass, or velocity in kg, g, lb and m/s, km/h, mph — with k...
mechanics↗
Mechanics · Mechanics
Muzzle Velocity Calculator
Calculate ideal speed equivalent of a stated projectile kinetic energy and projectile mass using the nonrelativistic ...
mechanics↗
Mechanics · Mechanics
Potential Energy Calculator
Calculate gravitational and elastic potential energy using U = mgh and U = ½kx². Results in joules and kilojoules for...
mechanics↗
Mechanics · Mechanics
Speed Distance Time Calculator
Free speed distance time calculator — solve v = d/t, d = v×t, or t = d/v across m/s, km/h, mph, kilometres, miles, se...
mechanics↗
Mechanics · Mechanics
Spring Force Calculator
Free Hooke's law calculator. Solve F = -kx for spring force, displacement, or spring constant and get elastic potenti...
mechanics↗
Mechanics · Mechanics
Work-Energy Calculator
Free work physics calculator. Compute mechanical work W = F·d·cos θ in joules from force, displacement, and angle. So...
mechanics↗
Mechanics · Mechanics
API Gravity Calculator
Calculate API gravity from relative density at the petroleum reference condition, without performing a temperature co...
mechanics↗
Mechanics · Mechanics
Dipole Moment Calculator
Calculate electric dipole-moment magnitude for two equal and opposite point charges separated by a stated distance wi...
mechanics↗
Mechanics · Mechanics
Friction Coefficient Calculator
Friction coefficient calculator: μ = F/N from measured friction and normal forces. Static vs kinetic values, typical ...
mechanics↗
Mechanics · Mechanics
Friction Force Calculator
Calculate limiting dry-friction force magnitude from an entered coefficient of friction and normal-force magnitude wi...
mechanics↗
Mechanics · Mechanics
Friction Loss Calculator
Calculate straight-pipe Darcy-Weisbach head loss from an entered Darcy friction factor, pipe geometry, mean velocity,...
mechanics↗
Mechanics · Mechanics
Impulse Calculator
Free impulse calculator using J = FΔt = Δp. Solve the impulse-momentum theorem for impulse, velocity change, and fina...
mechanics↗
Mechanics · Mechanics
Magnetic Dipole Moment Calculator
Calculate magnetic dipole-moment magnitude of a planar current loop from current, enclosed area, and turn count with ...
mechanics↗
Mechanics · Mechanics
Moment of Inertia Calculator
Free moment of inertia calculator for a rod, disc, cylinder, sphere, or hoop. Pick a shape and get I and radius of gy...
mechanics↗
Mechanics · Mechanics
Particles Velocity Calculator
Calculate particles velocity with a sourced formula, guarded inputs, a worked example, and clearly stated scope.
mechanics↗
Mechanics · Mechanics
Pendulum Period Calculator
Free pendulum period calculator using T = 2π√(L/g). Get period, frequency, and the small-angle approximation error at...
mechanics↗
Mechanics · Mechanics
Physical Pendulum Calculator
Calculate small-angle period of a rigid physical pendulum from pivot moment of inertia, mass, gravity, and centre-of-...
mechanics↗
Mechanics · Mechanics
Polar Moment Calculator
Calculate polar second moment of area for a solid or hollow circular cross-section from outer and inner diameters wit...
mechanics↗
Mechanics · Mechanics
Rotational Stiffness Calculator
Calculate linear rotational stiffness from an applied torque and the resulting angular deflection in radians with exp...
mechanics↗
Mechanics · Mechanics
Shear Wave Velocity Calculator
Calculate ideal shear-wave speed in a homogeneous isotropic elastic solid from shear modulus and mass density with ex...
mechanics↗
Mechanics · Mechanics
Simple Harmonic Motion Calculator
Free SHM calculator for a mass-spring oscillator. Get period, frequency, angular frequency, and maximum velocity and ...
mechanics↗
Mechanics · Mechanics
Specific Gravity Calculator
Specific gravity calculator: sample density ÷ reference density. Covers water-referenced SG, floating and sinking, an...
mechanics↗
Mechanics · Mechanics
Torsional Spring Calculator
Torsional spring calculator: T = κθ with degree-to-radian conversion built in — solve for torque, spring rate, or def...
mechanics↗
Mechanics · Mechanics
Torsional Stiffness Calculator
Calculate Saint-Venant torsional stiffness of a uniform prismatic member from shear modulus, torsion constant, and le...
mechanics↗
Mechanics · Mechanics
Alfvén Velocity Calculator
Calculate ideal-MHD Alfvén speed from magnetic field, mass density, and magnetic permeability using coherent SI inputs.
mechanics↗
Mechanics · Mechanics
Drift Velocity Calculator
Calculate carrier drift-speed magnitude from current, mobile-carrier number density, carrier charge magnitude, and co...
mechanics↗
Mechanics · Mechanics
Velocity Addition Calculator
Calculate one-dimensional special-relativistic composition of two same-direction subluminal speeds with explicit cohe...
mechanics↗
Thermodynamics

Thermodynamics· 31 calculators

Popular
Thermodynamics · Thermodynamics
Cv Liquid Flow Calculator
Calculate idealized fully turbulent liquid flow in US gallons per minute from valve Cv, pressure drop in psi, and liq...
thermodynamics↗
★ Editor's pick
Thermodynamics · Thermodynamics
Drag Equation Calculator
Drag equation calculator: D = ½C_Dρv²A gives drag force from drag coefficient, fluid density, speed, and area — and w...
thermodynamics↗
Thermodynamics · Thermodynamics
Enthalpy Calculator
Calculate thermodynamic enthalpy from internal energy plus pressure-volume product in coherent joule units with expli...
thermodynamics↗
Thermodynamics · Thermodynamics
Heat Transfer Calculator
Calculate steady overall heat-transfer rate from an entered overall coefficient, transfer area, and driving temperatu...
thermodynamics↗
Thermodynamics · Thermodynamics
Kinematic Viscosity of Air Calculator
Kinematic viscosity of air: Sutherland's law plus ideal-gas density give ν = μ/ρ at your temperature and pressure — t...
thermodynamics↗
Thermodynamics · Thermodynamics
Open Channel Flow Calculator
Calculate uniform SI Manning discharge from a supplied roughness coefficient, flow area, hydraulic radius, and energy...
thermodynamics↗
Thermodynamics · Thermodynamics
Specific Heat Calculator
Free specific heat calculator — solve Q = mcΔT for heat, mass, c, or temperature change. SI units, worked water examp...
thermodynamics↗
Thermodynamics · Thermodynamics
Stefan-Boltzmann Law Calculator
Calculate black-body radiation power with the Stefan-Boltzmann law. Enter temperature, area, and emissivity for step-...
thermodynamics↗
Thermodynamics · Thermodynamics
Valve Flow Coefficient Calculator
Valve Cv calculator: Cv = Q√(SG/ΔP) sizes a control valve from flow, allowable pressure drop, and specific gravity — ...
thermodynamics↗
Thermodynamics · Thermodynamics
Carnot Efficiency Calculator
Calculate max heat-engine efficiency with the Carnot formula η = 1 − Tc/Th. Supports Kelvin and Celsius, with work an...
thermodynamics↗
Thermodynamics · Thermodynamics
Combustion Reaction Calculator
Calculate combustion reaction with a sourced formula, guarded inputs, a worked example, and clearly stated scope.
thermodynamics↗
Thermodynamics · Thermodynamics
Conductivity to Resistivity Calculator
Calculate reciprocal conversion between electrical conductivity and electrical resistivity in coherent SI units with ...
thermodynamics↗
Thermodynamics · Thermodynamics
Heat Capacity Calculator
Calculate whole-object heat capacity from transferred sensible heat and the resulting nonzero temperature change with...
thermodynamics↗
Thermodynamics · Thermodynamics
Heat Transfer Coefficient Calculator
Calculate effective heat-transfer coefficient from heat rate, transfer area, and driving temperature difference with ...
thermodynamics↗
Thermodynamics · Thermodynamics
Heat of Combustion Calculator
Calculate released-heat magnitude from fuel mass and a user-supplied mass-specific gross or net heat of combustion wi...
thermodynamics↗
Thermodynamics · Thermodynamics
Hydraulic Conductivity Calculator
Calculate hydraulic conductivity from intrinsic permeability, fluid density, gravitational acceleration, and dynamic ...
thermodynamics↗
Thermodynamics · Thermodynamics
Hydraulic Gradient Calculator
Hydraulic gradient calculator: i = Δh/L, head loss per unit path length — the driving ratio in Darcy's law for ground...
thermodynamics↗
Thermodynamics · Thermodynamics
Hydraulic Jump Calculator
Calculate rectangular-channel conjugate downstream depth from upstream depth and upstream Froude number with explicit...
thermodynamics↗
Thermodynamics · Thermodynamics
Hydraulic Radius Calculator
Calculate hydraulic radius of an open or non-full flow section from flow area and wetted perimeter with explicit cohe...
thermodynamics↗
Thermodynamics · Thermodynamics
Hydraulic Retention Time Calculator
Calculate nominal hydraulic retention time from a control volume and a steady volumetric flow rate in matching SI uni...
thermodynamics↗
Thermodynamics · Thermodynamics
Isentropic Flow Calculator
Calculate ideal-gas isentropic temperature ratio from initial/final pressure and a supplied heat-capacity ratio with ...
thermodynamics↗
Thermodynamics · Thermodynamics
Joule Heating Calculator
Calculate electrical heat generated by a constant current through a constant resistance over a stated elapsed time wi...
thermodynamics↗
Thermodynamics · Thermodynamics
Lift Coefficient Calculator
Calculate dimensionless lift coefficient from lift force, fluid density, speed, and the explicitly chosen reference a...
thermodynamics↗
Thermodynamics · Thermodynamics
Orifice Flow Calculator
Calculate idealized incompressible liquid discharge through an orifice using a user-supplied discharge coefficient an...
thermodynamics↗
Thermodynamics · Thermodynamics
Thermal Conductivity Calculator
Calculate conductive heat-transfer rate with Fourier's law (Q = kAΔT/L). Get watts, BTU/hr, heat flux, and R-value fr...
thermodynamics↗
Thermodynamics · Thermodynamics
Thermal Diffusivity Calculator
Calculate thermal diffusivity from thermal conductivity, mass density, and specific heat capacity at a shared materia...
thermodynamics↗
Thermodynamics · Thermodynamics
Thermal Efficiency Calculator
Thermal efficiency calculator: η = useful output ÷ heat input × 100%. Compare engines and power cycles against typica...
thermodynamics↗
Thermodynamics · Thermodynamics
Thermal Equilibrium Calculator
Calculate adiabatic final equilibrium temperature of two bodies with constant positive heat capacities with explicit ...
thermodynamics↗
Thermodynamics · Thermodynamics
Thermal Stress Calculator
Calculate fully restrained uniaxial thermal-stress magnitude from Young's modulus, linear expansion coefficient, and ...
thermodynamics↗
Thermodynamics · Thermodynamics
Water Viscosity Calculator
Calculate water viscosity with a sourced formula, guarded inputs, a worked example, and clearly stated scope.
thermodynamics↗
Thermodynamics · Thermodynamics
Wheatstone Bridge Calculator
Calculate unknown resistance required to balance an ideal Wheatstone bridge from the other three arm resistances with...
thermodynamics↗
Molecular Biology

Molecular Biology· 11 calculators

Popular
Molecular Biology · Molecular Biology
DNA Concentration Calculator (A260)
Convert A260 absorbance to ng/µL for dsDNA, ssDNA or RNA, with total yield, 260/280 and 260/230 purity ratios and the...
molecular-biology↗
★ Editor's pick
Molecular Biology · Molecular Biology
GC Content Calculator (Primer)
Calculate GC content, AT content, 3' GC clamp, Wallace Td and molecular weight of a DNA primer, checked against Loren...
molecular-biology↗
Molecular Biology · Molecular Biology
PCR Annealing Temperature Calculator
Calculate PCR annealing temperature from primer sequences using nearest-neighbour Tm (SantaLucia 1998), with Taq and ...
molecular-biology↗
Molecular Biology · Molecular Biology
Codon Translation Calculator
Translate DNA or RNA to a peptide using NCBI genetic code tables 1, 2, 5 and 11, in any of the three forward reading ...
molecular-biology↗
Molecular Biology · Molecular Biology
DNA Copy Number & Molarity Calculator
Convert ng/µL of double-stranded DNA into copies per µL, nM and fmol using NIST-measured base-pair masses — plus the ...
molecular-biology↗
Molecular Biology · Molecular Biology
DNA to mRNA Converter
Transcribe DNA to mRNA the right way round. Choose coding or template strand, get the transcript, both DNA strands, l...
molecular-biology↗
Molecular Biology · Molecular Biology
Ligation Calculator
Work out how many ng of insert to add to your vector for a 3:1 (or any) molar ratio. Shows pmol of each, and solves b...
molecular-biology↗
Molecular Biology · Molecular Biology
Protein Concentration Calculator
Turn an A280 reading or a Bradford/BCA standard curve into mg/mL and µM. Predicts ε from Trp, Tyr and cystine using P...
molecular-biology↗
Molecular Biology · Molecular Biology
Restriction Digest Calculator
Find every cut site in a DNA sequence and get the fragment sizes, for a linear fragment or a circular plasmid. Enter ...
molecular-biology↗
Molecular Biology · Molecular Biology
Transformation Efficiency Calculator
Turn a colony count into cfu per µg of DNA, correcting for the fraction of the transformation you actually plated. Al...
molecular-biology↗
Molecular Biology · Molecular Biology
qPCR Efficiency Calculator
Convert a qPCR standard curve slope into amplification efficiency using the MIQE 2.0 equation, or fit the slope from ...
molecular-biology↗
Meteorology

Astronomy· 29 calculators

Popular
Astronomy · Astronomy
Hubble's Law Calculator
Convert recession velocity to distance with v = H₀d. H₀ is editable and every answer is shown at both Planck's 67.4 a...
astronomy↗
★ Editor's pick
Astronomy · Astronomy
Kepler's Third Law Calculator
Kepler's third law calculator in the harmonic ratio form — no mass, no G. Solve orbital period from distance, or dist...
astronomy↗
Astronomy · Astronomy
Light Year Calculator
Convert light-years to parsecs, astronomical units, kilometres and miles using the exact IAU definitions. 1 ly = 9,46...
astronomy↗
Astronomy · Astronomy
Luminosity Calculator
Work out a star's luminosity from radius and temperature, or from observed flux and distance, with bolometric magnitu...
astronomy↗
Astronomy · Astronomy
Orbital Velocity Calculator
Vis-viva orbital velocity calculator: speed at periapsis, apoapsis, any radius, or a circular orbit, plus escape spee...
astronomy↗
Astronomy · Astronomy
Parallax Distance Calculator
Turn a stellar parallax in milliarcseconds into a distance in parsecs, light-years, au and km — with the error range ...
astronomy↗
Astronomy · Astronomy
Schwarzschild Radius Calculator
Compute the event-horizon radius of any mass from r = 2GM/c², or invert it to get the mass. Horizon area, photon sphe...
astronomy↗
Astronomy · Astronomy
Telescope Magnification Calculator
Work out telescope magnification from focal lengths, or the eyepiece you need for a target power. Includes exit pupil...
astronomy↗
Astronomy · Astronomy
Angular Size Calculator
Angular diameter from size and distance, or either one back from the angle. Separate sphere and flat geometry, plus t...
astronomy↗
Astronomy · Astronomy
Apparent Magnitude Calculator
How many times brighter is one star than another? Convert between magnitude difference and flux ratio on the Pogson s...
astronomy↗
Astronomy · Astronomy
Black Hole Temperature Calculator
Hawking temperature, Bekenstein–Hawking entropy, radiated power and evaporation time from a black hole's mass — or so...
astronomy↗
Astronomy · Astronomy
Exoplanet Transit Depth Calculator
Transit depth in ppm from planet and star radii, or planet radius from an observed depth. Uses IAU nominal radii and ...
astronomy↗
Astronomy · Astronomy
Gravitational Time Dilation Calculator
Exact Schwarzschild time dilation between two static clocks, or one clock versus infinity. Microseconds per day, reds...
astronomy↗
Astronomy · Astronomy
Habitable Zone Calculator
All five Kopparapu habitable-zone boundaries from a star's luminosity and temperature, using the corrected erratum co...
astronomy↗
Astronomy · Astronomy
Julian Date Calculator
Convert a UTC instant to Julian Date, MJD, TJD, the J2000.0 offset and Julian centuries T. Julian or Gregorian calend...
astronomy↗
Astronomy · Astronomy
Moon Phase Calculator
Moon phase, illumination and age for any UTC instant, from true new-moon instants rather than a 29.5-day average, plu...
astronomy↗
Astronomy · Astronomy
Roche Limit Calculator
Roche limit calculator for rigid, rubble-pile and fluid satellites, with the Roche critical density and an inside-or-...
astronomy↗
Astronomy · Astronomy
Sidereal Time Calculator
Local and Greenwich sidereal time from any UTC instant and longitude, mean and apparent, with the equation of the equ...
astronomy↗
Astronomy · Astronomy
Star Lifetime Calculator
Estimate a star's main-sequence lifetime from its mass on the nuclear timescale, or invert it. Every model assumption...
astronomy↗
Astronomy · Astronomy
Stellar Magnitude Calculator
Convert between apparent magnitude, absolute magnitude and distance with m − M = 5 log d − 5 + A, including an option...
astronomy↗
Astronomy · Astronomy
Surface Gravity of a Planet Calculator
Compute a planet's surface gravity from its mass and radius, separate out the equatorial rotation term, and solve bac...
astronomy↗
Astronomy · Astronomy
Synodic Period Calculator
Synodic period calculator: time between successive oppositions or conjunctions from two sidereal periods, and the inv...
astronomy↗
Astronomy · Astronomy
Telescope Field of View Calculator
True field of view from an eyepiece field stop or apparent field, in degrees and arcminutes, plus star drift time and...
astronomy↗
Astronomy · Astronomy
Telescope Focal Ratio Calculator
Focal ratio from focal length and aperture, plus arcsec per pixel, Airy disc size, sampling verdict and the stops a f...
astronomy↗
Astronomy · Astronomy
Telescope Resolution Calculator
Dawes limit and Rayleigh criterion for any aperture, plus Airy disc size and the aperture you need to split a given d...
astronomy↗
Astronomy · Astronomy
Tidal Force Calculator
Tidal force calculator: differential gravity across a body, with exact near-side and far-side values, the transverse ...
astronomy↗
Astronomy · Astronomy
Weight on Other Planets Calculator
Enter one weight in any unit and see what you would weigh on Mercury, Venus, the Moon, Mars, Jupiter, Saturn, Uranus,...
astronomy↗
Astronomy · Astronomy
Age on Other Planets Calculator
How many orbits of the Sun each planet has completed in your lifetime, from JPL sidereal periods — plus your age in M...
astronomy↗
Astronomy · Astronomy
Telescope Limiting Magnitude Calculator
Faintest star an aperture reaches, from aperture gain plus your own sky and eye. Handles central obstruction and says...
astronomy↗
Optics