Free Trigonometry Calculators

Powerful interactive math tools for solving triangles, exploring the unit circle, and mastering trigonometric concepts. All calculators are 100% free with step-by-step solutions.

Pythagorean Theorem Calculator

The Pythagorean theorem calculator helps you find the missing side of a right triangle. Simply enter any two known sides (a, b, or c) and the calculator will solve for the third side using the formula a² + b² = c². This essential trigonometry tool also shows common Pythagorean triples and demonstrates the connection to the distance formula used in coordinate geometry.

a b c

Common Pythagorean Triples

3 - 4 - 5
5 - 12 - 13
8 - 15 - 17
7 - 24 - 25
9 - 40 - 41
11 - 60 - 61

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Master the Pythagorean theorem with interactive lessons, practice problems, and AI tutoring.

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Unit Circle Calculator

The unit circle calculator is the ultimate trigonometry reference tool. Enter any angle in degrees or radians to instantly see all six trigonometric function values: sine, cosine, tangent, cosecant, secant, and cotangent. The interactive visualization highlights your angle on the unit circle, shows the reference angle, identifies the quadrant, and displays exact values for common angles like 30°, 45°, 60°, and 90°.

1 i

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Master the unit circle with interactive lessons covering all angles and trig identities.

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SOHCAHTOA Calculator

The SOHCAHTOA calculator is your complete right triangle solver. This powerful trigonometry tool uses the famous mnemonic (Sine = Opposite/Hypotenuse, Cosine = Adjacent/Hypotenuse, Tangent = Opposite/Adjacent) to find all missing sides and angles. Whether you know one angle and one side, or two sides of the triangle, this calculator determines every measurement and shows you exactly which trig ratio was used in the solution.

b (adjacent) a (opposite) c (hypotenuse) A

SOHCAHTOA Mnemonic

SOH: sin(θ) = Opposite / Hypotenuse
CAH: cos(θ) = Adjacent / Hypotenuse
TOA: tan(θ) = Opposite / Adjacent

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Master SOHCAHTOA and all trig ratios with interactive practice problems and detailed explanations.

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Triangle Solver (Law of Sines & Cosines)

The triangle solver is an advanced trigonometry calculator that works with any triangle, not just right triangles. Using the Law of Sines and Law of Cosines, this tool can solve triangles when you know: three sides (SSS), two sides and the included angle (SAS), two angles and one side (ASA), or two angles and a non-included side (AAS). The calculator finds all missing sides and angles, computes the triangle's area, and displays an accurate visual representation.

Select a case above to begin

c a b A B C

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Master the Law of Sines, Law of Cosines, and advanced triangle solving techniques.

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11 More Interactive Calculators

Explore our full collection of interactive tools — converters, graphers, practice quizzes, word problem solvers, and identity references. Each calculator has its own dedicated page with educational content and step-by-step explanations.

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Unit Circle Explorer

Interactive unit circle with all standard angles, coordinates, and six trig function values. The essential trig visualization tool.

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Degree-Radian Converter

Instantly convert between degrees, radians, gradians, and turns. Visual unit circle display with common angle reference table.

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Reference Angle Finder

Find the reference angle for any angle in degrees or radians. Identifies quadrant, shows trig sign rules, and visualizes on the unit circle.

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Bearing & Navigation Calculator

Calculate bearings, headings, distances, and waypoints for navigation using trigonometric formulas. Used in aviation, sailing, and surveying.

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Angle of Elevation & Depression

Solve real-world problems involving looking up (elevation) or down (depression). Step-by-step solutions with interactive diagrams.

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Polar-Cartesian Converter

Convert between polar (r, θ) and Cartesian (x, y) coordinates with step-by-step solutions and interactive graph.

Sine Wave Playground

Explore amplitude, frequency, phase shift, and vertical shift with real-time interactive waveform visualization.

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Trig Function Grapher

Graph all six trig functions with adjustable amplitude, period, phase shift, and vertical offset. Compare transformations visually.

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Trig Identity Cheat Sheet

Every trigonometric identity organized by category with an interactive verifier. Pythagorean, double-angle, half-angle, and more.

Trig Speed Quiz

Race the clock across 4 difficulty levels! Practice unit circle values, identities, and conversions. Track your high scores.

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Word Problem Solver

Choose from 6 real-world trig scenarios — ladders, shadows, ramps, kites, and more — with step-by-step solutions and diagrams.