Angles Converter

Convert between degrees, radians, gradians, arcminutes, arcseconds, turns, military mils and other units of angle.

1 radian = 1 radian

Most used angle units

Popular angle conversions

What is angle?

An angle measures the amount of turn between two lines that meet at a point. The most familiar unit is the degree: a full circle is 360°, a right angle 90°. Mathematicians and physicists prefer the radian, the angle at which the arc of a circle equals its radius; a full circle is 2π radians, about 6.283.

Other units divide the circle differently: the gradian (400 per circle) was designed for decimal surveying, the military mil (6,400 per circle in NATO) makes range estimation easy, and navigators once used the 32 points of the compass. Astronomers measure tiny angles in arcminutes and arcseconds, 1/60 and 1/3,600 of a degree.

Degrees and radians

  • Radians to degrees: degrees = radians × 180/π (1 rad ≈ 57.2958°)
  • Degrees to radians: radians = degrees × π/180 (1° ≈ 0.0174533 rad)
  • Common angles: 30° = π/6, 45° = π/4, 60° = π/3, 90° = π/2, 180° = π, 360° = 2π
  • 1 degree = 60 arcminutes = 3,600 arcseconds

Angle units from smallest to largest

Every proportional angle unit on the site, ordered by size and expressed in radians.

  1. Microarcsecond 4.848137 × 10-12 rad
  2. Milliarcsecond 4.848137 × 10-9 rad
  3. Microradian 0.000001 rad
  4. Arcsecond 0.00000484814 rad
  5. Second of time 0.0000727221 rad
  6. Arcminute 0.000290888 rad
  7. NATO mil 0.000981748 rad
  8. Swedish streck 0.000997331 rad
  9. Milliradian 0.001 rad
  10. Warsaw Pact mil 0.0010472 rad
  11. Minute of time 0.00436332 rad
  12. Gradian 0.015708 rad
  13. Degree 0.0174533 rad
  14. Binary degree 0.0245437 rad
  15. Quarter point 0.0490874 rad
  16. Hexacontade 0.10472 rad
  17. Compass point 0.19635 rad
  18. Hour angle 0.261799 rad
  19. Zodiac sign 0.523599 rad
  20. Octant 0.785398 rad
  21. Radian 1 rad
  22. Sextant 1.0472 rad
  23. Quadrant 1.5708 rad
  24. Turn 6.28319 rad

All 24 angle units

Common

Astronomy & precision

Traditional & military

Frequently asked questions

How many degrees are in a radian?

One radian is 180/π degrees, about 57.2958°.

Why are there 360 degrees in a circle?

The number goes back to Babylonian astronomy. 360 is close to the number of days in a year and divides evenly by 2, 3, 4, 5, 6, 8, 9, 10, 12 and more.

What is a mil?

An angular mil divides a circle into 6,400 parts (NATO). At 1 km, 1 mil subtends about 1 m, which makes range and adjustment calculations easy.

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