Gradian to Radian Converter

Convert gradian to radian instantly. 1 gradian = 0.015708 radian.

1 Gradian =
Radian
From
To

Gradian to Radian Table

GradianRadian
1 grad0.015708 rad
5 grad0.07854 rad
10 grad0.15708 rad
30 grad0.471239 rad
45 grad0.706858 rad
90 grad1.413717 rad
180 grad2.827433 rad
360 grad5.654867 rad

Quick Answer

Formula: Radian = Gradian × 0.01571

Multiply any gradian value by 0.01571 to get radian.

Reverse: Gradian = Radian × 63.66

Worked Examples

1 grad
1 grad × 0.01571 = 0.01571 rad
Single unit reference.
45 grad
45 grad × 0.01571 = 0.7069 rad
45° — half a right angle.
90 grad
90 grad × 0.01571 = 1.414 rad
90° — one right angle.
180 grad
180 grad × 0.01571 = 2.827 rad
180° — a straight line / half circle.

Gradian to Radian Conversion Table

Common gradian values — factor: 1 grad = 0.01571 rad

Gradian (grad)Radian (rad)Context
1 grad0.01571 rad1 grad
5 grad0.07854 rad5 grad
10 grad0.1571 rad10 grad
25 grad0.3927 rad22.5°
50 grad0.7854 rad45°
100 grad1.571 rad90° right angle
150 grad2.356 rad135°
200 grad3.142 rad180° half circle
250 grad3.927 rad225°
300 grad4.712 rad270°
400 grad6.283 rad360° full circle
800 grad12.57 radTwo circles
1200 grad18.85 radThree circles
2000 grad31.42 radFive circles
4000 grad62.83 radTen circles

Mental Math Tricks

Exact factor

1 grad = 0.01571 rad. Memorize for instant estimates.

Key anchors

Right angle: 90° = 1.571 rad.

Reverse

Multiply result by 63.66 to recover the original grad value.

Who Uses This Conversion?

Surveyor (European)

Uses gradians for land surveying in France, Sweden, and other European countries.

Civil Engineer

Applies gradians in road gradient calculations where 100 grad = right angle is convenient.

Geodesist

Works with national coordinate systems in countries that standardized on gradians.

Cartographer

Uses gradians in French topographic mapping traditions.

Mining Engineer

Applies gradians for dip and strike measurements in some European mining standards.

Artillery Gunner

Uses gradians in some European military targeting and range calculation systems.

Frequently Asked Questions

About Gradian and Radian

Gradian (grad)

The gradian (also called gon or grade) divides a full circle into 400 equal parts, so a right angle equals exactly 100 gradians. It was introduced during the French Revolution as part of the decimal metric system reform in the 1790s.

Gradians are used primarily in surveying, civil engineering, and some European geodetic systems. The advantage: since a right angle = 100 grad, slope percentages and bearing calculations involve simple arithmetic.

Interesting fact: France briefly mandated decimal angles (gradians) in the 1790s alongside the metric system, but the gradian never achieved the same global adoption as the meter and kilogram.

Radian (rad)

The radian is the SI unit of angle, defined as the angle subtended at the center of a circle by an arc equal in length to the radius. It was formally adopted by the SI system in 1995, though it had been used in mathematics since the 18th century.

Radians simplify calculus and physics: derivatives of trigonometric functions, wave equations, and angular velocity formulas are all cleaner in radians. One full circle = 2π radians ≈ 6.2832 rad.

Interesting fact: The name 'radian' was coined by physicist James Thomson in 1873. At exactly 1 radian, the arc length equals the radius — the elegant geometric relationship that makes radians so mathematically natural.

About Gradian to Radian Conversion

Converting gradian to radian is essential in mathematics, physics, engineering, and surveying. Degrees are used in everyday contexts and navigation; radians are the standard in calculus and physics; gradians are common in European surveying. Having accurate conversions ensures correct results across disciplines.

Key reference: a right angle (90°) = 1.571 rad. A full circle (360°) = 6.283 rad. Reverse: 1 rad = 63.66 grad. Exact factor: 1 grad = 0.01571 rad.

All conversions use IEEE 754 double-precision arithmetic, accurate to at least 8 significant figures.