This polygon interior angle calculator helps when number of sides are already known and you want the interior angle quickly.
Informational calculator only. Verify important outputs independently before legal, tax, medical, engineering, safety-critical, contractual, employment, or compliance use.
Enter job values, review the estimate, then use the decision hints before ordering or quoting.
interior angle = ((n - 2) x 180) / nFor a regular polygon, divide the total interior-angle sum by the number of sides.
The polygon must have at least three sides.
This page is tuned for clean geometry checks during drafting or homework around regular polygon interior angle.
Next: polygon exterior angle.
Next: regular polygon central angle.
Keep more decimal places when the result will be reused in another formula, drawing, or comparison rather than read once and rounded.
Yes. The formula is stable and this tool only covers straightforward calculation.