Time Units

International System of Units (SI)

The basic unit of time measurement both in the International System of Units (SI) and in the GHS system is the second.

The units of time that are used today are historically formed and reflect astronomical observations of the rotation of the Earth around the Sun, and the Moon around the Earth.

• Century [c] = 100 yr
• Year [yr] = 365.25 d
• Week [wk] = 7 d
• Day [d] = 24 h
• Hour [h] = 60 min
• Minute [min] = 60 s
• Second [s] = 1000 ms
• Millisecond [ms] = 1000 μs