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Angle Converter - Convert Between Degrees, Radians, Gradians Online Free

Convert between degrees, radians, and gradians.

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Unit Converter
Angle Converter
Convert between degrees, radians, turns and other angle measures quickly.
About This Tool

What Is a Angle Converter?

An angle converter converts between different angle measurement units.

Supported Units

  • Degree — Standard unit. 1/360 of a full circle.
  • Radian — SI unit. 1 rad = 180/pi degrees.
  • Gradian — 1/400 of a full circle. Surveying.

How Does Angle Converter Work?

180 degrees = pi radians = 200 gradians. 1 degree = pi/180 radians.

How to Use This Tool

  1. Enter a numeric value — Type the measurement you want to convert.
  2. Select the source unit — Choose the unit you are converting from.
  3. Read the results — The tool instantly displays equivalents in every supported unit.

Try our Speed Converter or Energy Converter.

Use Cases

Mathematics

Convert between degrees and radians for trigonometry.

Engineering

Convert angles for CAD and surveying.

Privacy

All calculations are performed entirely in your browser using JavaScript. No data is sent to our servers. We do not store, log, or share any values you enter.

Uses exact conversion factors: 360 deg = 2pi rad = 400 grad.

AI Overview

An angle converter converts between degrees, radians, and gradians.

Quick Answers

Q:

Degrees in pi radians?

A:

180.

Q:

Degrees in 1 radian?

A:

~57.296.

Q:

Gradians in a circle?

A:

400.

Formula / Algorithm

Understanding the Angle Conversion Algorithm

The Angle Converter tool utilizes a straightforward mathematical formula to convert angles between different units, primarily degrees and radians. This conversion is essential in various fields such as mathematics, physics, and engineering, where angles need to be expressed in a format compatible with the specific requirements of the task at hand.

Mathematical Formula

The conversion between degrees and radians is based on the relationship where 180 degrees is equivalent to π radians. The formulae for conversion are as follows:

  • From Degrees to Radians: radians = degrees × (π / 180)
  • From Radians to Degrees: degrees = radians × (180 / π)

Variables Explanation

  • Degrees: The angle measurement in degrees, a unit of angular measure where a full circle is 360 degrees.
  • Radians: The angle measurement in radians, a unit of angular measure used in many areas of mathematics, where a full circle is 2π radians.
  • π (Pi): A mathematical constant approximately equal to 3.14159, representing the ratio of a circle's circumference to its diameter.

Step-by-Step Breakdown

  1. Identify the initial angle measurement and its unit (degrees or radians).
  2. Apply the appropriate formula based on the initial unit.
  3. Perform the multiplication to convert the measurement.
  4. Output the converted angle in the desired unit.

Practical Example

Consider converting 90 degrees to radians:

  1. Start with the formula for degrees to radians: radians = degrees × (π / 180).
  2. Substitute 90 for degrees: radians = 90 × (π / 180).
  3. Calculate the result: radians = 90 × 0.0174533 ≈ 1.5708 radians.

This calculation shows that 90 degrees is approximately equal to 1.5708 radians. This conversion is crucial when integrating angle measurements into trigonometric functions often used in calculus or physics.

How to Use the Angle Converter - Convert Between Degrees, Radians, Gradians Online Free

  1. Type the angle value you want to convert into the input field. Decimals and large numbers are supported.
  2. Choose your starting unit from the dropdown menu - for example degrees, radians (rad), or gradians (gon).
  3. See the value converted into every supported unit instantly, including turns, arcminutes, or arcseconds.

Live Examples

Input: 180 degrees
Output: 3.14159 radians

Explanation: Converts 180 degrees to radians using the formula radians = degrees × π / 180.

Input: 2 radians
Output: 114.5916 degrees

Explanation: Converts 2 radians to degrees using the formula degrees = radians × 180 / π.

Input: 90 degrees
Output: 100 gradians

Explanation: Converts 90 degrees to gradians using the formula gradians = degrees × 200 / 180.

Input: 200 gradians
Output: 180 degrees

Explanation: Converts 200 gradians to degrees using the formula degrees = gradians × 180 / 200.

Input: 1 radian
Output: 63.662 gradians

Explanation: Converts 1 radian to gradians using the formula gradians = radians × 200 / π.

Benefits

  • Instant Multi-Unit Conversion
  • Multiple Unit Systems
  • 100% Free to Use
  • Works on Any Device

Common Mistakes

  • Degrees vs radians: different scales
  • Gradians rarely used outside surveying
  • pi radians = 180 degrees exactly
  • Full circle: 360 deg = 2pi rad = 400 grad

Professional Tips

  • Programming languages often use radians
  • Conversion: deg x pi/180 = rad
  • Conversion: rad x 180/pi = deg
  • Navigation uses degrees; physics prefers radians

Common Use Cases

Mathematics

Convert for trigonometry.

Engineering

Convert for CAD and surveying.

Related Concepts

Degree

Standard unit. 1/360 of a full circle.

Radian

SI unit. 1 rad = 180/pi degrees.

Gradian

1/400 of a full circle. Surveying.

Frequently Asked Questions

180.

~57.296.

400.

References

Author

The ToolsConverters editorial team reviews and maintains all tool descriptions, how-to guides, and FAQ content to ensure accuracy and usefulness for everyday users.

Reviewed By

ToolsConverters Technical Reviewer

Technical review ensures that conversion factors, unit definitions, and formulas described on this page are accurate and current.

Last Updated


Accuracy Statement

This page was last reviewed for accuracy in August 2026. Conversion factors follow international standards (NIST, BIPM, ISO).

Editorial Process

Tool descriptions and guides are written by the editorial team, reviewed for technical accuracy, and updated periodically.

Educational Purpose

Explains angle measurement systems used in math, engineering, and navigation.

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