MATH · FREE TOOL
Triangle calculator · three sides
Solve a planar triangle’s area and angles from three side lengths.
Your inputs
Enter your values, then calculate.
Decimal-point numbers; displayed rounding does not change internal values. Calculations stay on this device.
YOUR RESULT
Make the numbers clear.
Save calculation JSON ↓Calculation breakdown
Scroll sideways to see every column. You can also focus the table and use the arrow keys.
How this calculation works
SSS only. Each pair of sides must sum to more than the third. Area uses Heron’s formula sqrt[s(s−a)(s−b)(s−c)] and angles use the cosine rule. All side inputs share a unit; area uses its square. This does not solve ambiguous SSA cases.
Check the assumptions
Use the stated units and conventions. This tool supports the workflow described here; it does not infer missing information or outside rules.