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Sources and Accuracy
Angle conversions use radian as the reference unit. Degree, arcminute, arcsecond, turn, and surveying units are converted through fixed factors.
Displayed results are rounded for readability. The calculator keeps enough precision for everyday use and switches to scientific notation for very large or very small values. Last reviewed: 2026-05-21.
About These Units
radian [rad]
Definition
The radian is the SI angle unit based on the radius and arc length of a circle.
History
Radians became standard in mathematics because they simplify trigonometric formulas and calculus.
Current use
Radians are used in mathematics, physics, engineering, programming, rotation, and angular velocity calculations.
degree [deg]
Definition
The degree is an angle unit equal to one 360th of a full turn.
History
Degrees come from sexagesimal angle division and have long use in geometry and astronomy.
Current use
Degrees are used for geometry, navigation, maps, construction, engineering, weather direction, and rotations.