Triangle Calculator
Solve a triangle's sides, angles, and area from known measurements.
Inputs explained
- Mode — Choose SSS (three sides known) or SAS (two sides plus the included angle).
- Side a — The length of side a.
- Side b — The length of side b.
- Side c — The length of side c (SSS mode).
- Included Angle B (°) — The angle between sides a and c, in degrees (SAS mode).
How to use it
- Fill in the fields above — each input has a hint describing exactly what to enter
- Press Calculate to get your result instantly, right on this page
- Copy the result, save the tool to favorites, or share and embed it anywhere
Understanding the result
Example: A triangle with sides 3, 4, 5 is right-angled with an area of 6.
Frequently asked questions
Is the Triangle Calculator free to use? Yes — it is completely free, with no sign-up, no download and no usage limits. You can use it as often as you need.
Is my data private? Yes. The calculation runs entirely in your browser — the values you enter are never sent to our servers, stored or shared with anyone.
What information do I need? Just the following: Mode, Side a, Side b, Side c, Included Angle B (°). Each field includes a hint explaining exactly what to enter.
Can I use it on my phone? Yes — the tool is fully responsive and works on any device, and the same calculator is available in the EasyWorkCalcs mobile app.
Privacy
Everything you enter into the Triangle Calculator is processed entirely in your browser. Nothing is uploaded, stored or shared — your data stays on your device.