The Revit Unit System uses the following base units:
| Base Unit | Unit in Revit | Unit System |
|---|---|---|
| Length | Feet (ft) | Imperial |
| Angle | Radian | Metric |
| Mass | Kilogram (kg) | Metric |
| Time | Seconds (s) | Metric |
| Electric Current | Ampere (A) | Metric |
| Temperature | Kelvin (K) | Metric |
| Luminous Intensity | Candela (cd) | Metric |
Note: Because Revit stores lengths in feet and other quantities in metric, a derived unit involving length uses a non-standard unit using the Imperial and the Metric systems. For example, force is measured in mass-length per time squared and is stored in kg-ft/s2