Degrees to Radians

Since 180° is π radians, multiply degrees by π/180. The second figure is the multiple of π, so you can match π/2 or 2π at a glance.

Your numbers

Angle (°)(°)

Radians

3.141593rad

Result

Formula

Radians = Angle (°) × π ÷ 180

Trig functions in nearly every programming language take radians — passing degrees silently gives wrong answers.

What to enter

Input	Default	Accepted range
Angle (°) (°)An angle in degrees; a full turn is 360°.	180	-3,600 ~ 3,600

Step by step

FormulaRadians = Angle (°) × π ÷ 180

With the default numbersRadians = 180 × π ÷ 180

AnswerRadians = 3.141593 rad

Quick reference table

Results when only Angle (°) (°) changes and everything else stays put.

Angle (°) (°)	Radians (rad)	Result
90	1.570796	0.5
135	2.356194	0.75
180	3.141593	1
270	4.712389	1.5
360	6.283185	2

What each result means

Result	At default values
Radians (rad)An angle in radians; a full turn is 2π.	3.141593
ResultWhat the formula gives back — the answer this page is for.	1

Common mistakes

Trig functions in nearly every programming language take radians — passing degrees silently gives wrong answers.

Glossary

Angle (°): An angle in degrees; a full turn is 360°.
Radians: An angle in radians; a full turn is 2π.
Result: What the formula gives back — the answer this page is for.

Frequently asked questions

QHow is Degrees to Radians calculated?

Radians = Angle (°) × π ÷ 180 — Since 180° is π radians, multiply degrees by π/180. The second figure is the multiple of π, so you can match π/2 or 2π at a glance.

QCan you walk through an example?

With Angle (°) 180°, the answer is Radians 3.141593rad.

QWhat do I need to enter?

Enter Angle (°). The result recalculates as you type, and an empty box counts as zero.

QHow much does the answer move if I change a number?

Changing only Angle (°) (°) moves the answer to Angle (°) (°) 90 → Radians (rad) 1.570796 and Angle (°) (°) 360 → Radians (rad) 6.283185. The table below lays out five steps.

QHow are the numbers rounded?

Money is shown to the nearest whole unit, percentages to one decimal place and everything else to two. What you see is rounded; the calculation itself carries the unrounded value forward.

QAnything to watch out for?

Trig functions in nearly every programming language take radians — passing degrees silently gives wrong answers.

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Keep your length units consistent across inputs — mixing centimetres and metres throws results far off.