Polygon Angle Calculator

If you want to calculate the interior and exterior angles of polygons that are regular, the polygon angle calculator can help you. Enter the numbers straight away, or read on to learn how to calculate angles in a polygon.
If you're unfamiliar with the difference between the interior and exterior angles of polygons, don't worry - we'll cover that too!

Before we learn how to calculate angles in a polygon, it's worth knowing what exactly we can determine. The two most important types are:

• Interior polygon angles - These lie inside the polygon at its vertices.
• Exterior polygon angles - They are defined outside the polygon between one of its sides and the extension of an adjacent side. They are also equivalent to the central angle of the regular polygon equal to 360° or 2π divided by its number of sides.

In regular polygons whose sides all have the same length, the angles of the same type are equal.

For a regular polygon with $n$ sides, the interior angle, $\alpha$, can be found using the formula:

You can calculate the exterior angle of a polygon or its central angle, $\beta$, using the following equation:

It may be helpful to remember that the exterior and interior polygon angles sum up to 180°. Therefore, you can write:

where we used the fact that $\pi = 180\degree$. Feel free to brush up on the angle conversion if there's any confusion! Both radians and degrees are fine to use but remember to keep the units consistent.
You can also save yourself the hassle and use the polygon angle calculator, which allows easy conversion between the units.

If you'd like to do more than calculate the interior and exterior angles of polygons, we've got plenty of tools that can assist you:

• Regular polygon calculator;
• Area of regular polygon calculator;
• Heptagon calculator;
• Heptagon area calculator;
• Dodecagon calculator;
• Dodecagon area calculator;
• Decagon calculator;
• Decagon area calculator; and
• Hexagon calculator.