This article uses Greek letters such as alpha (α), beta (β), gamma (γ), and theta (θ) to represent angles. Several different units of angle measure are widely used, including degrees, radians, and gradians (gons):

1 full circle (turn) = 360 degrees = 2π radians = 400 gons.

The following table shows the conversions and values for some common angles:

Results for other angles can be found at Trigonometric constants expressed in real radicals.

Unless otherwise specified, all angles in this article are assumed to be in radians, but angles ending in a degree symbol (°) are in degrees. Per Niven's theorem multiples of 30° are the only angles that are a rational multiple of one degree and also have a rational sine or cosine, which may account for their popularity in examples.

The following table shows the conversions and values for some common angles:

Results for other angles can be found at Trigonometric constants expressed in real radicals.

Unless otherwise specified, all angles in this article are assumed to be in radians, but angles ending in a degree symbol (°) are in degrees. Per Niven's theorem multiples of 30° are the only angles that are a rational multiple of one degree and also have a rational sine or cosine, which may account for their popularity in examples.