UnitDimensions

UnitDimensions[unit] returns a list of base dimensions associated with the specified unit.

• UnitDimensions[quantity] returns a list of base dimensions associated with the unit of the specified quantity.

Examples

Dimensions of meters:

UnitDimensions["Meters"]
(* {{"LengthUnit", 1}} *)

Velocity dimensions:

UnitDimensions["Meters/Seconds"]
(* {{"LengthUnit", 1}, {"TimeUnit", -1}} *)

From a quantity:

UnitDimensions[Quantity[5, "Newtons"]]

Please visit the official Wolfram Language Reference for more details.