- Volume Calculator
- Area Calculator
- Perimeter Calculator
- Surface Area Calculator
- Circle Calculator
- Rectangle Calculator
- Triangle Calculator
-
Law of Cosines Angle CalculatorFind the angle of a triangle from its three side lengths using the law of cosines. Enter sides a, b, and c to get angle C in degrees and radians.
-
Area of a Triangle (Base × Height) CalculatorCalculate the area of any triangle from its base and height using A = ½ × b × h. Fast, free, and accurate for geometry, math homework, and design.
-
Missing Angle from Law of Sines CalculatorFind a triangle's unknown angle using the Law of Sines: A = arcsin(a·sin B / b). Enter two sides and one opposite angle to solve instantly.
-
Missing Side from Law of Sines CalculatorFind an unknown triangle side using the Law of Sines: enter a known side, its opposite angle, and the angle opposite the missing side.
-
Arctangent (Arctan) CalculatorFind the angle θ from the opposite and adjacent sides using θ = arctan(opposite/adjacent). Get the result in both degrees and radians instantly.
-
Right Triangle Perimeter from Two Legs CalculatorFind the perimeter of a right triangle from its two legs. Enter leg a and leg b to get the hypotenuse and total perimeter instantly.
-
Heron's Formula CalculatorFind the area of any triangle from its three side lengths using Heron's formula. Free calculator showing area, semi-perimeter and perimeter instantly.
-
30-60-90 Triangle Sides from Short LegFind all sides of a 30-60-90 triangle from the short leg. Computes long leg (short·√3), hypotenuse (2·short), perimeter, and area instantly.
-
45-45-90 Triangle Hypotenuse CalculatorFind the hypotenuse of a 45-45-90 right triangle from a leg length using h = leg × √2. Also gives perimeter and area instantly.
-
Triangle Third Angle CalculatorFind the third angle of any triangle instantly. Enter two known angles and get the missing angle using C = 180° − A − B. Free and accurate.
-
Distance Between Two Points CalculatorFind the distance between two points (x1,y1) and (x2,y2) on a coordinate plane — the length of a triangle side — using the distance formula.
-
Sine, Cosine & Tangent of an Angle CalculatorCalculate sin(θ), cos(θ) and tan(θ) for any angle in degrees or radians. Instant trigonometric function values with a clear worked example.
-
Area of Isosceles Triangle from Base and Equal SidesCalculate the area, height, and perimeter of an isosceles triangle from its base and two equal sides using the exact geometric formula.
-
Triangle Perimeter & Semiperimeter CalculatorCalculate the perimeter and semiperimeter of a triangle from its three sides, with a Heron's formula area check and triangle inequality validation.
-
Law of Cosines Calculator (Side c)Find the third side c of any triangle using the Law of Cosines: c = √(a² + b² − 2ab·cos C). Enter two sides and the included angle in degrees.
-
Arcsine CalculatorFind an angle from the opposite side and hypotenuse using arcsine. Enter both sides to get the angle in degrees and radians instantly.
-
Arccosine Angle CalculatorFind the angle of a right triangle from its adjacent side and hypotenuse using θ = arccos(adjacent / hypotenuse). Results in degrees and radians.
-
Hypotenuse Calculator from Two LegsFind the hypotenuse of a right triangle from its two legs using the Pythagorean theorem c = √(a² + b²). Also shows area and perimeter.
-
Triangle Classification by Sides CalculatorClassify a triangle as equilateral, isosceles, or scalene from its three side lengths. Free instant calculator with a built-in valid-triangle check.
-
Angle Between Two Lines CalculatorFind the acute angle between two straight lines from their slopes m₁ and m₂ using θ = arctan(|(m₁−m₂)/(1+m₁m₂)|). Get the result in degrees and radians.
-
Scalene Triangle Perimeter CalculatorCalculate the perimeter of a scalene triangle by adding its three unequal sides: P = a + b + c. Fast, accurate, free online tool.
-
Triangle Median CalculatorCalculate the three medians of a triangle from its side lengths using the median length formula. Free, instant, and accurate triangle median solver.
-
Incircle of a Triangle CalculatorFind the inradius and incircle of a triangle from its three sides. Computes inradius r = Area/s with Heron's formula, plus incircle area and circumference.
-
Triangle Side from Two Sides & Included Angle (Law of Cosines)Find the third side of a triangle from two sides and the included angle using the Law of Cosines: c = √(a² + b² − 2ab·cosC). Free, instant.
