# How many base SI units are there in SI unit system?

International systems of units are known as SI units. The SI units are represented without the help of other quantities known as fundamental quantities such as length, temperature etc.

The SI system has seven base units, and they are

• unit of length,
• unit of mass,
• unit of time,
• unit of electric current,
• unit of thermodynamic temperature,
• unit of amount of substance,
• unit of luminous intensity.

These units pertain to the seven fundamental scientific quantities: metre, kilogram, second, ampere, kelvin, mole, and candela.