Right Triangle Calculator – Solve Sides & Angles

Solve any right triangle: hypotenuse, missing sides, angles, area & steps. Highlight a problem on any page to solve it.

Right Triangle Calculator helps you solve right triangle problems quickly, with the working shown so you can follow every step. Enter any two known values, such as two sides or one side and an angle, and the extension finds the rest: the missing sides, both acute angles, the area, the perimeter and the altitude to the hypotenuse. A small diagram, drawn to scale, updates as you type. FEATURES • Step-by-step working Each answer shows the formulas used and how the numbers were substituted, so you can check your own working. • Exact answers When a side is a square root, you get the simplified exact value as well as the decimal, for example 2√13 ≈ 7.2111. • Solve highlighted text Select a triangle problem on a web page, right-click and choose "Solve right triangle". The answer appears in a small card next to the text. You can also use the keyboard shortcut Alt+Shift+S. • Type the problem in words In the popup, you can type a problem the way you would say it, such as "hypotenuse 10, angle 30°", and the fields fill in for you. • Check three sides Enter three lengths to find out whether they form a right triangle. If they don't, the extension tells you whether the triangle is acute or obtuse. • Formula sheet A Formulas tab keeps the main right triangle formulas and common exact values in one place. • History Your recent calculations are saved on your device, so you can reopen them later. • Units and dark mode Use metric or imperial units, and degrees or radians. The extension follows your system's light or dark theme. HOW TO USE IT 1. Click the extension icon in the toolbar, or press Alt+Shift+T. 2. Enter any two values, or type the problem in words. 3. Read the answer, open the steps, or copy the result. PRIVACY All calculations happen inside your browser. The extension doesn't collect or share any personal data, and it doesn't run on pages in the background. It only reads text you have highlighted, and only when you ask it to solve that text. Your history is stored on your own device. MORE HELP Each result has a "Full solution" button that opens the same problem on righttrianglecalculator.online, where you'll find more detailed calculators, guides and worked examples. Questions or suggestions? You can reach us through the contact page on the website.