How do you convert degrees to radians?

Multiply the degree value by pi divided by 180. For example, 90 degrees equals 90 x pi / 180, or pi over 2 radians. The converter also shows the pi multiple so exact trigonometry values are easier to recognize.

How do you convert radians to degrees?

Multiply the radian value by 180 divided by pi. For example, pi radians equals 180 degrees. Decimal radian inputs are converted with JavaScript's Math.PI value, so the degree result is displayed as a rounded decimal.

What is a normalized angle?

A normalized angle is wrapped into one full turn. In degrees, this page normalizes into the 0 to 360 degree range. That helps when an angle is negative or larger than one rotation but represents the same terminal side on the unit circle.

When should I use radians instead of degrees?

Radians are usually preferred in higher-level trigonometry, calculus, arc length, and unit circle work because they connect angle measure directly to circle radius and arc length. Degrees are often easier for basic geometry drawings, bearings, and introductory angle descriptions.

Why does the converter show pi multiples?

Many trigonometry angles are written exactly as multiples of pi, such as pi over 6, pi over 4, pi over 3, and pi over 2. Showing the pi multiple helps users connect decimal radians to exact unit circle notation instead of treating radians as only a decimal number.

Angle Converter

Degrees to Radians Converter

Convert degree measure to radians and radians back to degrees. The result also shows pi multiples and normalized angles for unit circle and trigonometry work.

Unit circle values Radians guide

Live converter

Degrees and radians inputs

Convert degrees to radians and radians to degrees with the pi multiple visible for exact trigonometry work.

Degrees

deg

Radians

rad

Radians from degrees

3.141593

Pi multiple

1pi

Degrees from radians

180 deg

Normalized degrees

180 deg

Normalized radians

3.141593

Formula

Degrees and radians conversion formulas

Degrees to radians

radians = degrees x pi / 180

Radians to degrees

degrees = radians x 180 / pi