Table 1: Quantity brief

Table 2: Supported units  Basis units for a unit system are printed in boldface.

SI classifies The plane angle as supplementary unit. Considering that plane angle is generally expressed as the ratio between two lengths, SI specifies the quantity plane angle as dimensionless derived quantities. Therefore, the supplementary units radian is to be regarded as dimensionless derived units which may be used or omitted in the expressions for derived units.

Ad (1): A degree (in full, a degree of arc, arc degree, or arcdegree), usually denoted by ° (the degree symbol), is a measurement of plane angle, representing 1⁄360 of a full rotation; one degree is equivalent to π/180 radians. It is not an SI unit, as the SI unit for angles is radian, but it is an accepted unit.