Base Units
The fundamental units of measurement. Base units are defined independently and form the foundation of all other derived units.
The International System of Units (SI) defines seven base units from which all other units are derived. The table below shows all 32 supported measurement units, grouped by physical category.
Absorbed Dose
| Name | Symbol |
|---|---|
| Gray | Gy |
Amount of Substance
| Name | Symbol |
|---|---|
| Mole | mol |
Catalytic Activity
| Name | Symbol |
|---|---|
| Katal | kat |
Data Quantity
| Name | Symbol |
|---|---|
| bit | b |
| byte | B |
Electric Capacitance
| Name | Symbol |
|---|---|
| Farad | F |
Electric Charge
| Name | Symbol |
|---|---|
| Coulomb | C |
Electric Conductance
| Name | Symbol |
|---|---|
| Siemens | S |
Electric Current
| Name | Symbol |
|---|---|
| Ampere | A |
Electric Potential
| Name | Symbol |
|---|---|
| Volt | V |
Electric Resistance
| Name | Symbol |
|---|---|
| Ohm | Ω |
Energy
| Name | Symbol |
|---|---|
| Joule | J |
Equivalent Dose
| Name | Symbol |
|---|---|
| Sievert | Sv |
Force
| Name | Symbol |
|---|---|
| Newton | N |
Frequency
| Name | Symbol |
|---|---|
| Hertz | Hz |
Illuminance
| Name | Symbol |
|---|---|
| Lux | lx |
Inductance
| Name | Symbol |
|---|---|
| Henry | H |
Length
| Name | Symbol |
|---|---|
| Meter | m |
Luminous Flux
| Name | Symbol |
|---|---|
| Lumen | lm |
Luminous Intensity
| Name | Symbol |
|---|---|
| Candela | cd |
Magnetic Flux
| Name | Symbol |
|---|---|
| Weber | Wb |
Magnetic Flux Density
| Name | Symbol |
|---|---|
| Tesla | T |
Mass
| Name | Symbol |
|---|---|
| Gram | g |
Opinionated choice: The SI defines the kilogram (kg) as the base unit for mass. This site uses the gram (g) instead, as it aligns more naturally with everyday usage and avoids the conceptual oddity of a base unit that carries a prefix by definition. All mass conversions are expressed relative to grams accordingly.
Plane Angle
| Name | Symbol |
|---|---|
| Radian | rad |
Power
| Name | Symbol |
|---|---|
| Watt | W |
Pressure
| Name | Symbol |
|---|---|
| Pascal | Pa |
Radioactivity
| Name | Symbol |
|---|---|
| Becquerel | Bq |
Solid Angle
| Name | Symbol |
|---|---|
| Steradian | sr |
Temperature
| Name | Symbol |
|---|---|
| Celsius | °C |
| Kelvin | K |
Time
| Name | Symbol |
|---|---|
| Second | s |
Transmission Rate
| Name | Symbol |
|---|---|
| Bit per second | bit/s |