maratoolHow to convert degrees to radians (and gradians)
Type an angle — read degrees, radians, gradians, arcminutes, or turns instantly.
Trig functions want radians, CSS transforms take degrees or turns, and surveying uses gradians. The Angle Converter converts between all angle units instantly.
How it works
- Pick units — "Degree (°)" to "Radian (rad)", or any other pair.
- Type a value — the result updates as you type, with swap and copy.
- Copy — one click, with "Copied!" feedback.
Angle conversion factors
Every unit converts through the degree (the base unit). To convert A → B, multiply by A's factor and divide by B's:
| Unit | = this many degrees |
|---|---|
| Degree (°) | 1 |
| Radian (rad) | 57.295779513082 |
| Milliradian (mrad) | 0.057295779513 |
| Gradian (gon) | 0.9 |
| Arcminute (′) | 0.016666666667 |
| Arcsecond (″) | 0.000277777778 |
| Turn (tr) | 360 |
When you need it
The conversions you use daily as a developer: 180° = π rad ≈ 3.14159 rad, 1 rad ≈ 57.2958°, and CSS accepts deg, rad, grad, and turn — 0.25turn = 90° = 100grad.
Sources & methodology
Conversion factors follow BIPM SI Brochure; exact-by-definition factors are marked in the tool itself. All math runs client-side in your browser — nothing is uploaded.
More conversion guides
- How to calculate TV and monitor dimensions from the diagonal
- How to convert Hz to RPM and rad/s
- How to convert square feet to square meters (and any area unit)
Or browse everything at once in the new unit & sizing converters roundup.