Online Tool Store
Triangle Solver
Solve SSS, SAS, ASA, AAS, and right triangles from validated inputs, with missing values, diagram, area, perimeter, and formulas.
🔒 This tool runs entirely in your browser. Your files are never uploaded to a server.
Known measurements
What do you know?
Solved triangle
Side a
5
Side b
6
Side c
7
Angle A
Angle B
Angle C
Area
Perimeter
Method
How it works
- Select the measurement pattern you already know.
- Enter the sides and/or angles shown for that pattern.
- Review every solved side and angle, area, perimeter, diagram, and method.
FAQ
What information is enough to solve a triangle?
Three sides (SSS), two sides and their included angle (SAS), two angles and one side (ASA/AAS), or the two legs of a right triangle uniquely determine the cases supported here.
What is the triangle inequality?
The sum of any two side lengths must be greater than the third. If this rule fails, those measurements cannot form a triangle.
How is area calculated?
After all sides are known, the calculator uses Heron’s formula: area equals the square root of s(s−a)(s−b)(s−c), where s is half the perimeter.
Are calculations sent anywhere?
No. All trigonometry and validation run directly in your browser.
How we compare
| Feature | Online Tool Store | Scientific calculator | Manual formulas |
|---|---|---|---|
| SSS, SAS, ASA/AAS, right | ✓ | Manual | Manual |
| Validation and diagram | ✓ | No | No |
| Area and perimeter | Automatic | Manual | Manual |