Converter

plane angle · International · Modern

radian

radexact
Record
M432
Definition quality
Standardized
Conversion mode
multiplicative
Calculator
Fully calculable

Definition

Radian is the coherent SI unit of plane angle.

History & use

Used throughout mathematics, physics, and engineering.

Modern use

Still in current use in International. Beyond that, modern use is context-dependent and varies by region and measurement system.

Did you know?

A full turn is 2π rad.

Sources & evidence

Related measurements

plane angle · International · Modern

Non-SI unit accepted for use with the SI; 1° = π/180 rad.

plane angle · International · Modern

1 arcminute = 1/60 degree = π/10800 rad.

plane angle · International · Modern

1 arcsecond = 1/60 arcminute = π/648000 rad.