Rotation

Angle Converter

Convert angles between degrees, radians, gradians, and more.

Result

0.017453Radian

Degree1
Radian0.017453
Gradian1.111111
Arcminute59.99988
Arcsecond3,599.99712
Turn0.002778

Base unit: degree. All conversions calculated from this common reference.

What is the Angle Converter?

An angle converter is a tool that translates angular measurements from one unit to another. The most common conversions are between degrees (360 per full rotation), radians (2π per full rotation, used in calculus and physics), gradians (400 per full rotation, used in surveying), and turns (1 = one complete rotation).

How it works

The converter uses fixed mathematical relationships between angle units. Since all units measure the same rotation, the tool multiplies your input by the appropriate conversion factor. For example, degrees to radians multiply by π/180; radians to degrees multiply by 180/π. Enter any angle in any unit and the tool instantly calculates all equivalent values.

Degrees to Radians: radians = degrees × (π/180); Radians to Degrees: degrees = radians × (180/π); Degrees to Gradians: gradians = degrees × (400/360); Gradians to Degrees: degrees = gradians × (360/400); Degrees to Turns: turns = degrees / 360

π (pi) ≈ 3.14159 is the mathematical constant relating circles to their diameter. The conversion factors come from the fact that 360° = 2π radians = 400 gradians = 1 full turn.

Examples

InputResultNotes
45 degrees0.785 radians, 50 gradians, 0.125 turns45° is 1/8 of a full rotation, a common angle in geometry and carpentry
π radians (3.14159)180 degrees, 200 gradians, 0.5 turnsπ radians equals a straight angle, the most important angle in trigonometry
100 gradians90 degrees, 1.571 radians, 0.25 turnsGradians are used in surveying; 100 gradians = a right angle

How to use the Angle Converter

  1. Enter your angle value in the input field
  2. Select or confirm the unit of your input (degrees, radians, gradians, or turns)
  3. Click Convert or press Enter
  4. View all equivalent values displayed instantly
  5. Copy any result to paste into your project or notes
  6. Repeat with new angles as needed

Benefits

  • Instant conversions save time versus manual calculation
  • Eliminates rounding errors when switching between units
  • Supports all major angle units in one tool
  • Useful for mathematics, physics, engineering, and programming
  • Shows formulas so you can learn and verify the math
  • Free and requires no sign-up or installation

Tips & common mistakes

Common mistakes

  • Forgetting that π radians ≈ 3.14159 radians, not 180 radians (degrees and radians have different scales entirely)
  • Confusing gradians with degrees; 90° = 100 gradians, not 90 gradians
  • Rounding prematurely in intermediate steps; let the converter handle full precision

Tips

  • Bookmark this tool if you work regularly with angles; it's faster than typing π/180 into a calculator
  • Radians are the default unit in most programming languages and scientific fields; learn to think in radians for calculus
  • Visualize angles as fractions of a circle: 90° = 1/4 turn, 180° = 1/2 turn, 360° = 1 full turn

Frequently asked questions

Why do radians exist if we already have degrees?

Radians are the natural unit for calculus and trigonometry because they relate arc length directly to the radius: arc length = radius × angle in radians. This makes derivatives and integrals much cleaner.

What are gradians and who uses them?

Gradians (also called gons) divide a circle into 400 equal parts instead of 360. Surveyors and some European engineers use gradians because 100 gradians = a right angle, making decimal calculations cleaner.

Can I convert negative angles?

Yes, negative angles represent rotation in the opposite direction (clockwise instead of counterclockwise). The conversion formulas work identically for negative values.

How precise are these conversions?

The tool uses full floating-point precision (typically 15-17 significant digits), well beyond the precision needed for any real-world application.

What's the difference between angle and rotation?

An angle measures the separation between two lines or directions (0–360°). A rotation is motion through that angle. The units are identical; the tool converts both.

Why is 360 degrees in a full circle?

Ancient Babylonians chose 360 because it divides evenly by 2, 3, 4, 5, 6, 8, 9, 10, 12, 15, and 18, making fractions of a circle easy to calculate by hand.

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FreeTooz Editorial Team · Last reviewed July 2026

Reviewed for accuracy. Results are estimates for general information and are not professional (medical, financial or legal) advice.