Issue No. 001 ▪ v4.2.1 ▪ Audited 12/04/2026

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Auditedv4.2.1

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§ 01

Featured this week.

MATH · STATISTICSTier 1

Z-Score Calculator

Free z-score calculator: enter value, mean, and standard deviation to get z, percentile, and a two-sided p-value with...

math↗ Open
FINANCE · COMMERCIAL-REAL-ESTATETier 1

Yield Maintenance Calculator

Calculate commercial mortgage yield maintenance penalties. Enter balance, rate, Treasury yield, and term for prepayme...

finance↗ Open
SCIENCE · MECHANICSTier 1

Work-Energy Calculator

Free work physics calculator. Compute mechanical work W = F·d·cos θ in joules from force, displacement, and angle. So...

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EVERYDAY · WRITINGTier 1

Word Counter

Free word counter. Get instant character, word, sentence, paragraph counts plus reading and speaking time for essays,...

everyday↗ Open
SCIENCE · METEOROLOGYTier 1

Wind Chill Calculator

Free wind chill calculator using the 2001 NWS/Environment Canada formula. Get apparent temperature in °F or °C plus f...

science↗ Open
MATH · STATISTICSTier 1

Weighted Average Calculator

Calculate weighted averages from values and weights. Essential for grades, portfolio returns, and survey analysis.

math↗ Open
§ 02

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§ 03

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finance · fixed-income
Treasury Bill Yield Calculator
Price a Treasury bill and compare discount yield, holding-period return, and investment yield from face value and days.
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math · geometry
Triangle Solver Calculator
Free triangle calculator: solve any triangle from SSS, SAS, or ASA inputs. Returns all sides, all angles, area, and p...
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math · trigonometry
Trigonometry Calculator
Free trig calculator: compute sin, cos, tan, csc, sec, cot for any angle in degrees or radians. Unit circle values, r...
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everyday · conversions
Unit Converter
Free unit converter for length, mass, volume, temperature, time, area, and speed. SI and US customary units with NIST...
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health · nutrition
Vitamin D Intake Calculator
Calculate daily vitamin D needs in IU and micrograms. Get RDA, upper limits, and deficiency correction doses based on...
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health · fitness
VO2 Max Calculator
Estimate VO2 max from the Cooper 12-minute run, Rockport walk test, or heart-rate ratio. ACSM fitness rating, max HR,...
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