🔄Degrees to Radians Converter
Convert between degrees, radians, and gradians, with an exact π fraction form.
Free Degrees to Radians Converter
Our free degrees to radians converter instantly converts an angle between degrees, radians, and gradians, all from a single input. It also shows the exact π fraction form of the angle in radians — for example 90° becomes π/2 rather than a rounded decimal — which is exactly the form used in trigonometry and calculus coursework.
A live unit circle diagram plots the angle so you can see its position visually, whichever unit you entered it in. Degrees are the everyday unit for measuring angles, radians are the standard unit in mathematics because they relate arc length directly to radius, and gradians (400 per full turn) are occasionally used in surveying and some European countries.
Built for trigonometry, precalculus, and calculus students who need quick, exact angle conversions. No sign-up, no downloads — just instant results.
About the Degrees to Radians Converter
Features
Three-way conversion
Degrees, radians, and gradians, all from one input.
Exact π fraction form
See 90° as π/2, not just a rounded decimal.
Unit circle diagram
A visual marker for where your angle sits on the circle.
Negative and large angles
Works for any value, including negative angles and angles past 360°.
Frequently Asked Questions
How do I convert degrees to radians?
Multiply degrees by π/180. Enter your value in degrees and the calculator shows the radian equivalent instantly, both as a decimal and an exact π fraction.
What is a gradian?
A unit where a full circle is 400 gradians instead of 360 degrees or 2π radians. It's occasionally used in surveying.
What does the π fraction form show?
The exact radian value as a reduced fraction of π, e.g. 90° = π/2, rather than the rounded decimal 1.5708.
Can I enter a negative angle?
Yes, negative angles are converted correctly and shown on the unit circle diagram in the clockwise direction.
Can I enter an angle greater than 360°?
Yes, the conversion works for any value; the unit circle diagram shows the equivalent position after wrapping around.
How do I convert radians to degrees?
Multiply radians by 180/π. Switch the unit selector to Radians and enter your value.
Why use radians instead of degrees?
Radians relate arc length directly to radius (arc = radius × angle in radians), which simplifies calculus and many physics formulas.
Does the unit circle diagram update live?
Yes, it redraws immediately as you type.
Is my data stored?
No; all conversion happens locally in your browser.
Is it free?
Completely free, no sign-up or limits.