Formula
- Use the units shown beside each field.
- Results update automatically whenever you change an input.
- Displayed values use up to four decimal places, or scientific notation for very small or large numbers. Calculations use standard floating-point arithmetic; exact integer and fraction tools identify their own precision rules.
- Nondegenerate planar triangles. Exterior means the angle formed by extending one adjacent side, not the reflex angle.
Example Calculation
- Interior angle A: 60 °
- Interior angle B: 50 °
A=60° and B=50° give C=70°; adjacent exterior angles are 120°, 130° and 110°.
Frequently asked questions
How do I use this calculator?
Enter interior angle a, interior angle b. The result updates automatically. Use Reset to restore the example values.
What method does it use?
C=180°−A−B; each adjacent exterior angle=180°−interior angle.. Nondegenerate planar triangles. Exterior means the angle formed by extending one adjacent side, not the reflex angle.
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.