90 Degrees to Radians

90° = π/2 rad

90 degrees equals π/2 rad, which is about 1.570796 radians.

Step by step

Multiply by π/180: 90 × π/180.
Simplify the fraction: π/2 rad.
As a decimal (π ≈ 3.14159): 1.570796 rad.

Details

Radians (π form): π/2 rad
Radians (decimal): 1.570796
Gradians: 100
Turns: 0.25
sin / cos / tan: 1 / 0 / not defined
Position: On an axis

How it works

A full turn is 360 degrees or 2π radians, so 180° equals π radians. To convert degrees to radians, multiply by π/180 and simplify the fraction; to convert back, multiply by 180/π. Radians are the standard angle unit in mathematics, physics and programming languages, where trigonometric functions expect their input in radians.

Nearby values

Degrees	Radians
30°	π/6 rad (0.5236)
45°	π/4 rad (0.7854)
60°	π/3 rad (1.0472)
75°	5π/12 rad (1.309)
90°	π/2 rad (1.5708)
105°	7π/12 rad (1.8326)
120°	2π/3 rad (2.0944)
135°	3π/4 rad (2.3562)
150°	5π/6 rad (2.618)

Related conversions

Frequently asked questions

What is 90 degrees in radians?

π/2 rad ≈ 1.570796 rad.

How do you convert 90° to radians?

Multiply 90 by π/180.

What are sin, cos and tan of 90°?

1 / 0 / not defined (sin / cos / tan).

How many degrees is 1.5708 radians?

About 90°.