ASA Triangle Calculator

°
Enter angle a in °.
°
Enter angle b in °.
units
Enter included side c in units.
Math

ASA Triangle: calculate results from explicit inputs, with a formula and worked example.

Formula

C = 180°−A−B; a = c sin A/sin C; b = c sin B/sin C

Example Calculation

Example inputs
  • Angle A: 30 °
  • Angle B: 60 °
  • Included side c: 10 units

Angles 30° and 60° enclosing side c = 10 give sides 5 and approximately 8.6603.

Method references

Frequently asked questions

How do I use this calculator?

Enter angle a, angle b, included side c. The result updates automatically. Use Reset to restore the example values.

What method does it use?

C = 180°−A−B; a = c sin A/sin C; b = c sin B/sin C. Euclidean geometry. Use one consistent length unit; areas and volumes use its square and cube. Degenerate shapes are rejected. Very thin shapes may lose floating-point precision.

Why might a rounded result differ?

The calculation keeps full numeric precision internally, then rounds the displayed result. Rounding intermediate steps by hand can produce a slightly different answer.

Are my inputs saved online?

No. This calculator processes your inputs in your browser. A recently used list stores only calculator names on this device, not your entered values.

Check the assumptions and units before using this result. Read about calculation methods.