Radians to degrees

Type an angle in radians: a fraction of π like `3π/4` or `3pi/4`, or a plain number like `1.5`. The degrees appear straight away, and when the answer isn't a whole number it's also given in degrees, minutes and seconds.

Swap goes the other way, or use the degrees to radians converter.

Multiply by 180/π. When the angle is written with π, the π cancels and the arithmetic is easy. 3π/4 × 180/π is 3/4 × 180, which is 135°.

Without π, divide by π as a number, or multiply by about 57.29578. One radian is 57.29578°, or 57° 17′ 44.81″. 1.5 radians is about 85.94°.

The idea is older than the name. Roger Cotes worked with it before he died in 1716, and his cousin Robert Smith published the first known value of one radian in degrees in 1722. The word itself first appeared in print on 5 June 1873, in exam questions James Thomson set at Queen's College, Belfast. Thomas Muir at St Andrews had been wavering between "rad", "radial" and "radian", and settled on the last after consulting Thomson in 1874. Some textbooks went on calling it circular measure for years.