Degrees to Radians Converter
Convert any angle in degrees to radians. radians = degrees × π/180.
Result
90° in radians
1.57079633
≈ π/2.
- Conversion factorπ / 180 ≈ 0.0174533
- Multiple of ππ/2
- Decimal1.5707963268
Step-by-step
- 90° × (π / 180) = 90 × 0.01745329 = 1.57079633 rad.
How to use this calculator
- Enter angle in degrees.
- Read the equivalent in radians (and as a multiple of π).
About this calculator
Degrees and radians are two ways to measure angles. 180° = π radians. To convert degrees to radians, multiply by π/180. Common values: 30° = π/6, 45° = π/4, 60° = π/3, 90° = π/2, 180° = π, 360° = 2π.
Frequently asked
In calculus, derivatives of trig functions are simpler in radians: d/dx sin(x) = cos(x) only when x is in radians. Engineering frequently uses radians too.
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