From resolving a right triangle to applying the Law of Cosines for oblique cases, this collection covers the full range of trig calculations. The Sine Calculator, Cosine Calculator, and Arctan Calculator handle individual function values, while the Right Triangle Calculator solves for any unknown side or angle in one go.
Browse the full list or flip to the Trending tab to see which tools other users are reaching for. Everything is free, needs no account, and works on any device.
- Fraction Calculator
- Matrix Calculator
- Slope Calculator
- Algebra Calculator
- Trigonometry Calculator
- Percentage Calculator
- Probability Calculator
-
Amplitude, Period & Phase Shift CalculatorFind amplitude, period, phase shift, and vertical shift of y = a·sin(bx − c) + d. Enter a, b, c, d and get all transformations instantly.
-
Bearing Between Two Points CalculatorCalculate the initial true bearing (forward azimuth) in degrees between two latitude/longitude coordinates using the great-circle atan2 formula.
-
Linear Velocity from Angular Velocity CalculatorCalculate linear (tangential) velocity from radius and angular velocity using v = r·ω. Enter radius in meters and ω in rad/s to get speed in m/s.
-
Arc Length Calculator (s = rθ)Calculate the arc length of a circle from its radius and central angle using s = rθ. Supports angles in radians or degrees, with instant results.
-
Find All Six Trig Functions from One RatioEnter one trig ratio (sin, cos, tan, etc.) and the quadrant of θ to instantly find all six trigonometric functions using the Pythagorean identity.
-
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.
-
Trig Ratio from Sides CalculatorFind sin, cos, tan, csc, sec and cot of an angle from right-triangle side lengths. Hypotenuse auto-computed from the two legs via Pythagoras.
-
Diagonal of a Rectangle CalculatorFind the diagonal of a rectangle from its length and width. Also computes the diagonal angle, perimeter, and area instantly using the Pythagorean theorem.
-
Distance from Point to Line CalculatorCalculate the perpendicular distance from a point (x₀, y₀) to a line ax + by + c = 0 using d = |ax₀+by₀+c|/√(a²+b²). Free and instant.
-
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.
-
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.
-
Right Triangle Legs from Hypotenuse and Angle CalculatorFind both legs of a right triangle from the hypotenuse and an acute angle. Computes opposite = c·sinθ and adjacent = c·cosθ instantly.
-
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.
-
Vector Cross Product CalculatorCompute the cross product a × b of two 3D vectors: get the result vector components, its magnitude |a×b|, and the angle θ between the vectors.
-
Shadow Length CalculatorCalculate the shadow length cast by any object from its height and the sun's elevation angle. Free, instant shadow length calculator using trigonometry.
-
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.
-
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.
-
Trigonometric Equation SolverSolve sin θ = k, cos θ = k or tan θ = k. Get the principal value and the general solution θ = nπ + (−1)ⁿ·asin(k) for any integer n.
-
Amplitude, Period, Phase Shift & Midline CalculatorFind amplitude, period, phase shift and midline of any sine or cosine function y=A·sin(Bx−C)+D instantly. Free trig graph analysis tool.
-
Trig Identity Verifier Calculator — Pythagorean Identity (sin²θ + cos²θ = 1)Verify sin²θ + cos²θ = 1 and find cos θ from sin θ using cos θ = ±√(1−sin²θ). Pick the quadrant to choose the correct sign.
-
Sin Cos Tan CalculatorCalculate sine, cosine and tangent of any angle in degrees or radians. Instant sin θ, cos θ, tan θ values plus the angle converted to radians.
-
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.
Frequently asked questions
What trigonometric calculations can I find here?
The collection covers the core trig functions — sine, cosine, tangent, and their inverses (arcsin, arccos, arctan) — plus the Law of Cosines for non-right triangles and a full Right Triangle Calculator that solves for any unknown side or angle from just two known values.
How accurate are the trigonometry results?
All tools use standard trigonometric definitions and are tested against established reference values, making them dependable for coursework. For structural engineering, surveying, or any safety-critical application, verify your calculations against the governing standard and have a qualified engineer review the work.
Is there a fee to use these calculators?
Every trigonometry calculator here is completely free with no sign-up or subscription required. Open any tool, enter your angle or side values, and get the result instantly. No registration is needed.
Does the site log or save my inputs?
No — all calculations run locally in your browser. Nothing you type is sent to our servers, stored, or shared with any third party. Close the page and your entries are gone.
Which trig calculators are the most popular on the site?
The list is ranked by actual visitor usage, so the most popular tools appear at the top. The Trending tab shows which calculators are seeing the most activity right now, and Recently Added surfaces the newest tools in the collection.
