Pure mathematics.

Free distance formula calculator: enter two points (x1, y1) and (x2, y2) and get the Euclidean distance, midpoint, sl...

Free area and perimeter calculator for rectangles, squares, triangles, parallelograms, trapezoids, and circles — with...

Free area of a circle calculator: enter the radius to get area (πr²), circumference (2πr), and diameter (2r), with wo...

Free area of a rectangle calculator: enter length and width to get area, perimeter, and diagonal instantly, with work...

Calculate circle circumference from radius or diameter. Uses the exact definition π = 3.141592653589793 for precise g...

Calculate ellipse area with A = πab using semi-major and semi-minor axes. Supports metric and imperial units with exa...

Free pythagorean theorem calculator: solve a right triangle for the hypotenuse or a missing leg, plus area and perime...

Solve a right triangle from any two knowns: two legs, a leg and the hypotenuse, or a side and an angle. Get both acut...

Free slope calculator: enter two points and get slope m, y-intercept b, rise, run, and angle in degrees, with the ful...

Free triangle calculator: solve any triangle from SSS, SAS, or ASA inputs. Returns all sides, all angles, area, and p...

Free volume calculator for cube, rectangular prism, sphere, cylinder, and cone. Get volume and surface area instantly...

Enter any one measurement of a 30-60-90 triangle — a side, the area or the perimeter — and get every other side plus ...

Enter one measurement of a 45-45-90 triangle — a leg, the hypotenuse, the area or the perimeter — and get every side ...

Calculate aaa triangle with a sourced formula, guarded inputs, a worked example, and clearly stated scope.

Calculate aas triangle with a sourced formula, guarded inputs, a worked example, and clearly stated scope.

Calculate abc triangle with a sourced formula, guarded inputs, a worked example, and clearly stated scope.

Calculate acute triangle with a sourced formula, guarded inputs, a worked example, and clearly stated scope.

Free arc length calculator: enter radius and central angle (degrees or radians) to get arc length and sector area, wi...

Quadrilateral area calculator: split on a known diagonal and apply Heron's formula to both triangles — sides alone ne...

Calculate base of a triangle with a sourced formula, guarded inputs, a worked example, and clearly stated scope.

Find the centroid of a triangle from its three vertex coordinates. Returns the centroid point, all three median lengt...

Find a circle's chord from the radius and central angle, the distance to the centre, or the arc rise — and get the ra...

Calculate circle center with a sourced formula, guarded inputs, a worked example, and clearly stated scope.

Calculate circle measurements with a sourced formula, guarded inputs, a worked example, and clearly stated scope.

Calculate circle theorems with a sourced formula, guarded inputs, a worked example, and clearly stated scope.

Calculate circumcenter of a triangle with a sourced formula, guarded inputs, a worked example, and clearly stated scope.

Calculate classifying triangles with a sourced formula, guarded inputs, a worked example, and clearly stated scope.

Calculate complementary angles with a sourced formula, guarded inputs, a worked example, and clearly stated scope.

Calculate cubic in cylinder with a sourced formula, guarded inputs, a worked example, and clearly stated scope.

Calculate cubic yards cylinder with a sourced formula, guarded inputs, a worked example, and clearly stated scope.

Calculate diagonal of rectangle with a sourced formula, guarded inputs, a worked example, and clearly stated scope.

Calculate dimensions of a rectangle with a sourced formula, guarded inputs, a worked example, and clearly stated scope.

Solve an equilateral triangle from any single measurement — side, perimeter, area, height, inradius or circumradius —...

Calculate frequency polygon with a sourced formula, guarded inputs, a worked example, and clearly stated scope.

Find the golden-ratio partner of any side. Enter the short side, long side, area, perimeter or diagonal and get every...

Calculate great circle with a sourced formula, guarded inputs, a worked example, and clearly stated scope.

Calculate height of a square pyramid with a sourced formula, guarded inputs, a worked example, and clearly stated scope.

Calculate hexagonal pyramid with a sourced formula, guarded inputs, a worked example, and clearly stated scope.

Paste any list of x,y corners and get the polygon's area by the shoelace formula, plus its perimeter, true centroid a...

Solve an isosceles triangle from any two knowns — legs and base, base and height, or a leg and the apex angle. Get he...

Calculate lateral area trapezoidal prism with a sourced formula, guarded inputs, a worked example, and clearly stated...

Calculate lateral surface area cylinder with a sourced formula, guarded inputs, a worked example, and clearly stated ...

Free midpoint calculator: enter two points (x1,y1) and (x2,y2) to get the exact midpoint and segment length, with wor...

Calculate oblique triangle with a sourced formula, guarded inputs, a worked example, and clearly stated scope.

Calculate obtuse triangle with a sourced formula, guarded inputs, a worked example, and clearly stated scope.

Calculate perimeter quadrilateral with a sourced formula, guarded inputs, a worked example, and clearly stated scope.

Generate Pythagorean triples with Euclid's formula from m and n, or check whether three whole numbers form a triple a...

Calculate quarter circle with a sourced formula, guarded inputs, a worked example, and clearly stated scope.

Calculate radius of sphere with a sourced formula, guarded inputs, a worked example, and clearly stated scope.

Calculate rectangular prism with a sourced formula, guarded inputs, a worked example, and clearly stated scope.

Area, perimeter, apothem, circumradius, across flats and angles for any regular polygon. Solve from a side, an apothe...

Calculate right circular cone with a sourced formula, guarded inputs, a worked example, and clearly stated scope.

Calculate right cylinder with a sourced formula, guarded inputs, a worked example, and clearly stated scope.

Calculate right rectangular pyramid with a sourced formula, guarded inputs, a worked example, and clearly stated scope.

Calculate right square pyramid with a sourced formula, guarded inputs, a worked example, and clearly stated scope.

Calculate scalene triangle with a sourced formula, guarded inputs, a worked example, and clearly stated scope.

Find the scale factor between two similar triangles, solve every missing side, and get the perimeter and area ratios....

Calculate sin triangle with a sourced formula, guarded inputs, a worked example, and clearly stated scope.

Calculate special right triangles with a sourced formula, guarded inputs, a worked example, and clearly stated scope.

Calculate square feet of rectangle with a sourced formula, guarded inputs, a worked example, and clearly stated scope.

Square in a circle calculator: the inscribed square's diagonal equals the diameter, so side = r√2 and area = 2r² — th...

Square pyramid calculator: volume = base² × height ÷ 3, base area, and face slant height from side and height — with ...

Calculate ssa triangle with a sourced formula, guarded inputs, a worked example, and clearly stated scope.

Calculate supplementary angles with a sourced formula, guarded inputs, a worked example, and clearly stated scope.

Calculate tangent circle with a sourced formula, guarded inputs, a worked example, and clearly stated scope.

Solve a trapezoid from its two parallel sides plus either both legs or the height. Get exact area, perimeter, height,...

Free triangle area calculator: choose base × height, Heron's formula (SSS), or SAS to find the area, with worked step...

Calculate triangle congruence with a sourced formula, guarded inputs, a worked example, and clearly stated scope.

Calculate triangle degree with a sourced formula, guarded inputs, a worked example, and clearly stated scope.

Find the height of a triangle from three sides, two sides and the included angle, or the area and a base. Returns the...

Calculate triangle length with a sourced formula, guarded inputs, a worked example, and clearly stated scope.

Calculate triangle proportionality theorem with a sourced formula, guarded inputs, a worked example, and clearly stat...

Calculate triangle side with a sourced formula, guarded inputs, a worked example, and clearly stated scope.

Calculate triangle sum theorem with a sourced formula, guarded inputs, a worked example, and clearly stated scope.

Calculate triangle vertices with a sourced formula, guarded inputs, a worked example, and clearly stated scope.

Calculate triangular prism with a sourced formula, guarded inputs, a worked example, and clearly stated scope.

Truncated cone calculator: frustum volume V = πh(R² + Rr + r²)/3 from the two radii and height — buckets, funnels, an...

Find the circle through three points or around a triangle. Returns the circumradius, the circumcentre, the circle's a...

Check whether three lengths can form a triangle, or find the range the third side must fall in. Also classifies it as...