Part of the Units & Conversions suite · 14 calculators

Gradians to Radians Converter

Convert gradians to radians — 100 gradians is π/2. Results update as you type; exact factors shown.

One gradian (gon) is 0.0157 radians — see the exact factor, not a rounded rule of thumb.

Direction
Results update as you type
Results
1 gon in radians
0.0157 rad
Conversion factor
Reverse conversion
In radian (base unit)
Reviewed September 2026. Exact conversion factors from the BIPM SI Brochure and NIST SP 811; Australia is fully metric under the National Measurement Act 1960; imperial units appear only in trade with the US and in older documents.
No account required · Google Analytics off unless allowedCalculator arithmetic runs in your browserResults update as you type
All calculations run 100% in your browser. The calculator code does not submit your figures to GlobalCalc to obtain a result.
About angle conversion

How the gradians to radians converter works

Angles convert through the radian. A full turn is 2π radians = 360° = 400 gon = 6,400 NATO mils. A degree is 60 arcminutes, an arcminute 60 arcseconds.

Australia is fully metric under the National Measurement Act 1960; imperial units appear only in trade with the US and in older documents.

Common angle conversions

FromToUnits
10 gon0.1571 radgradian (gon) to radians
25 gon0.3927 radgradian (gon) to radians
50 gon0.7854 radgradian (gon) to radians
100 gon1.5708 radgradian (gon) to radians
150 gon2.3562 radgradian (gon) to radians
200 gon3.1416 radgradian (gon) to radians
250 gon3.927 radgradian (gon) to radians
300 gon4.7124 radgradian (gon) to radians
350 gon5.4978 radgradian (gon) to radians
400 gon6.2832 radgradian (gon) to radians
500 gon7.854 radgradian (gon) to radians
1,000 gon15.708 radgradian (gon) to radians

Units in this converter and their exact factors

UnitSymbolOne unit in radians
degree°0.0174532925 radian
radianrad1 radian
gradian (gon)gon0.0157079633 radian
arcminute0.0002908882 radian
arcsecond0.0000048481 radian
turn (revolution)rev6.2831853072 radian
NATO mil (1/6400 turn)mil0.0009817477 radian

Frequently asked questions about angle conversion

How many radians is 100 gradians?

π/2, about 1.5708 — one right angle.

How many gradians in a full turn?

400.

Why was the gradian invented?

During French metrication, to give the right angle a round value of 100.

Is it still used?

Rarely — surveying in some European countries, and as a calculator mode.

What is 400 gradians in radians?

2π, a full turn.

Where these figures come from

Last checked: September 2026. Conversion factors are fixed by definition and do not change with tax years or regulations.