Frequently Asked Questions
Common questions about the Triangle Calculator.
How does the triangle calculator work?
Enter any 3 known sides/angles, pick the matching case, and it solves for the rest with steps shown.
What cases does it support?
SSS, SAS, ASA, AAS, and SSA (including the ambiguous case).
What is the SSA ambiguous case?
When you know two sides and a non-included angle, there can be 0, 1, or 2 valid triangles — the calculator detects and shows all valid solutions.
Does it show the steps?
Yes, full Law of Sines / Law of Cosines working with your actual numbers.
What if my triangle is invalid?
It's flagged clearly (e.g. sides that violate the triangle inequality), never a silent wrong answer.
Does it calculate area and perimeter?
Yes, both are shown alongside all sides and angles.
Can I use radians instead of degrees?
Yes, toggle between degrees and radians.
Is it free and unlimited?
Completely free, no sign-up or limits.
Is my data stored?
No, everything runs locally in your browser.
Does it work on mobile?
Yes, fully responsive including the diagram.