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Area, perimeter and diagonal calculators for the standard 2D figures — triangles, quadrilaterals, ellipses and polygons. The…
Everything derived from a circle: area and circumference, plus arc length, sector and segment areas, chords and rings. Heavily…
Solve any triangle from the parts you know — right triangles via SOHCAHTOA and the Pythagorean theorem, oblique triangles via the…
Dedicated solvers for equilateral, isosceles and the two special right triangles, plus triangle heights, medians and centers…
Evaluate and invert the six trig functions, convert between angle units, and reduce angles to reference or coterminal form. The…
Volume, surface area and slant-height calculators for spheres, cylinders, cones, prisms, pyramids, frustums and caps. Used for…
Analytic geometry in the plane and in 3D: distance, midpoint, slope, line equations, intersections and coordinate-system…
Most used in geometry & trigonometry
- Triangle Area CalculatorThis calculator finds the area of any triangle by whichever route your measurements allow: base and perpendicular height, three…
- Rectangle Area & Perimeter CalculatorEnter any two of a rectangle's defining quantities and this calculator returns the rest: area, perimeter, diagonal, aspect…
- Trapezoid Area & Perimeter CalculatorEnter the two parallel sides and the perpendicular height and this calculator returns the area, the midsegment and — if…
- Hexagon Area & Across-Flats CalculatorGive this calculator any single dimension of a regular hexagon — the side, the across-flats width a wrench reads, the…
- Circle Area CalculatorEnter whichever circle measurement you have — radius, diameter, circumference or even the area itself — and this…
- Circumference CalculatorCircumference is the distance once around a circle, and it is one multiplication from the diameter: C = πd. This calculator…
- Arc Length CalculatorArc length is the distance measured along a curve rather than across it, and it is one multiplication away once the angle is in…
- Pythagorean Theorem Calculatora² + b² = c² relates the three sides of any right triangle, and this calculator runs it in all three directions…
- Right Triangle Calculator (SOHCAHTOA)A right triangle is fully determined by any two of its parts other than the two acute angles, and this calculator solves it…
- Law of Sines CalculatorThe law of sines says every side of a triangle bears the same ratio to the sine of its opposite angle, and that single equality…
- Law of Cosines CalculatorThe law of cosines solves the two triangle cases the law of sines cannot start from: two sides with the angle between them…
- 30-60-90 Triangle CalculatorA 30-60-90 triangle has its sides locked in the exact ratio 1 : √3 : 2, so one measurement gives you all of them with no…