The International System of Units (SI) is the most commonly used system of units for measuring physical quantities. SI is used in most countries of the world and almost always in science.
The table below provides information on the 7 basic SI units: the name and designation ( and English/International), as well as the measured value.
| Unit name | designation | Measured value | ||
| Engl. | Engl. | |||
| Second | Second | с | s | Time |
| Meter | meter | м | m | Length (or distance) |
| Kilogram | Kilogram | kg | kg | Weight |
| Ampere | Ampere | А | A | Electric current strength |
| Kelvin | Kelvin | К | K | Thermodynamic temperature |
| Mole | mole | mole | mol | Amount of substance |
| Candela | Candle | cd | cd | The power of light |
Note: Even if a country uses a different system, certain coefficients are set for its elements, allowing them to be converted to SI units.