Convert RADIANS to DEGREES, Free
Type any RADIANS value and see the DEGREES result instantly. No button press needed.
How to convert RADIANS to DEGREES
Radians and degrees are both ways to measure angles. A full circle is 2*pi radians or 360 degrees. To convert radians to degrees, multiply by 180/pi (approximately 57.2958). For example, pi/4 radians = 45 degrees; pi/2 radians = 90 degrees; pi radians = 180 degrees. This conversion runs instantly in your browser using JavaScript's built-in Math.PI constant for maximum precision.
Radians are the natural unit for mathematics and physics because they simplify calculus formulas involving trigonometric functions. The derivative of sin(x) in radians is simply cos(x); in degrees it would require a conversion factor. Programming languages and scientific calculators use radians by default for trig functions. But most people think in degrees for practical angle descriptions, which is why the conversion is needed constantly when translating between code and human understanding.
Enter the angle in radians
Type a numeric value in radians, or use common fractions of pi (e.g., enter 'pi/4' or '0.7854'). The converter accepts both forms.
Read the degree result
The result appears instantly: radians x (180/pi). Common angles (30, 45, 60, 90, 180, 270, 360 degrees) are labeled for reference.
Use the quick reference table
Common radian-to-degree conversions (pi/6, pi/4, pi/3, pi/2, pi, 2pi) are displayed in a reference table below the calculator.
Reverse if needed
Enter a degree value to get radians: multiply degrees by pi/180.
Frequently asked questions
What is the formula to convert radians to degrees?
Degrees = radians x (180 / pi). Pi is approximately 3.14159265.
How many radians is 180 degrees?
Exactly pi radians (approximately 3.14159).
How many radians is 90 degrees?
Pi/2 radians (approximately 1.5708).
Why do programming languages use radians instead of degrees?
Because radians make mathematical formulas simpler. The Taylor series for sin(x) and all its derivative relationships work correctly only when x is in radians.
What is 1 radian in degrees?
1 radian = 180/pi = approximately 57.2958 degrees.