Convert an angle between degrees, radians and gradians for maths and engineering.
Try an example
Load a ready-made sample into this tool and run it. Every result you see is calculated live by the tool itself — nothing here is a pre-written answer.
Sample: value: 180; from: deg; to: rad
How to Use
- Enter an angle value.
- Choose the current unit and the target unit.
- Read the converted angle.
What this angle converter does
This angle converter converts angles between degrees, radians, and gradians. Enter a value, choose the unit it is in and the unit you want, and read the result. Angles show up in mathematics, engineering, surveying, graphics, and game development work, and different fields favour different units, so a quick conversion keeps formulas, drawings, and code consistent without manual factor juggling.
The relationships behind the conversion
A full turn is 360 degrees, 2π radians, or 400 gradians, and half a turn is 180 degrees, exactly π radians, or 200 gradians. Radians are the unit most mathematics and programming libraries expect, degrees are the everyday unit on protractors and maps, and gradians appear in some surveying traditions. Converting through these fixed relationships keeps the angle identical, only its unit changes.
Good to know
Conversions use exact factors, with 180 degrees equal to π radians, and results are rounded to six decimal places. That precision is far beyond measuring instruments, but if you chain many conversions in a calculation, tiny rounding at the last decimal can accumulate slightly.
Frequently asked questions
How many radians is 90 degrees?
Ninety degrees is π/2 radians, about 1.570796 radians. Enter 90, convert from degrees to radians, and the tool shows the value rounded to six decimal places for use in your formula.
What is a gradian used for?
A gradian divides a right angle into 100 parts, so a full turn is 400 gradians. It appears in some surveying and engineering contexts, mainly in parts of Europe, rather than in everyday measuring.
Can I convert radians back to degrees?
Yes, the converter works in both directions between any two of the three units. Choose radians as the starting unit and degrees as the target to turn a formula result back into a familiar angle.
How to use Angle Converter
- Enter an angle value.
- Choose the current unit and the target unit.
- Read the converted angle.
Limitations
Conversions use exact factors (180 degrees = PI radians); results round to 6 decimal places.