Enter an angle, pick the unit you have and the unit you want, and read the answer instantly — plus the same angle in every other unit at once. It covers the everyday degree, the radian used in maths and programming, gradians, full turns, and the arcminutes and arcseconds used in navigation and astronomy. Everything runs in your browser.
In all units
- Degree (°)1 °
- Radian (rad)0.017453 rad
- Gradian (gon)1.111111 gon
- Turn (revolution)0.002778 turn
- Arcminute (′)60 ′
- Arcsecond (″)3,600 ″
How it works
Each unit is defined by how many radians it equals, and every conversion goes through the radian as a shared base. A full circle is 2π radians, 360 degrees, 400 gradians or 1 turn, so one degree is π/180 radians. Your value is turned into radians and then into the target unit.
Degrees split further: one degree is 60 arcminutes (′) and one arcminute is 60 arcseconds (″), so a degree is 3,600 arcseconds. Because π is irrational, converting a tidy degree value to radians gives a non-terminating decimal — results are shown to six decimal places, which is ample for trigonometry and most engineering.
Practical examples
A right angle in radians
90 degrees is π/2 ≈ 1.570796 radians — the value a programming language’s sin/cos functions expect. Enter 90, from degrees, to radians.
Radians back to degrees
A result of 1 radian is about 57.2958 degrees. Convert radians to degrees to read a calculation output in a unit you can picture.
Gradians on a survey instrument
Some surveying tools use gradians, where a right angle is exactly 100 gon. Convert 100 gradians to degrees to confirm it’s 90°.
Frequently asked questions
How do I convert degrees to radians?
Multiply degrees by π/180. So 180° = π ≈ 3.141593 rad and 90° = π/2 ≈ 1.570796 rad. Enter the degree value and read the radian row — the tool uses the full-precision value of π.
How do I convert radians to degrees?
Multiply radians by 180/π (about 57.29578). One radian is roughly 57.3°. This is the conversion you need when a maths library returns an angle in radians and you want to display degrees.
What is a radian?
The angle subtended at the centre of a circle by an arc equal in length to the radius. A full circle is 2π radians. Radians are the natural unit for calculus and are what trig functions in most programming languages expect.
What is a gradian?
Also called a gon or grade, it divides a right angle into 100 parts, so a full circle is 400 gradians. It’s used in some surveying and engineering contexts because it makes right angles and percentages of a quarter-turn tidy.
What are arcminutes and arcseconds?
Subdivisions of a degree: one degree is 60 arcminutes (′), and one arcminute is 60 arcseconds (″). They’re used for small, precise angles in astronomy, navigation and optics — for example a telescope’s resolving power.
What is a turn?
One full rotation — 360°, 2π radians or 400 gradians. It’s handy when you think in whole or fractional revolutions, such as “a quarter turn” (0.25 turn = 90°).
Does it accept the decimal comma?
Yes. You can type 1,5 or 1.5 and both mean one and a half. Grouping separators in pasted numbers are handled too.
How precise are the results?
Conversions run at full floating-point precision using JavaScript’s value of π and are shown to six decimal places with trailing zeros removed — enough for trigonometry, graphics and engineering.
Are the values I enter sent anywhere?
No. The conversion runs entirely in your browser; nothing is uploaded and analytics never receives the numbers.
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