Everyday Math

Time Units

Different ways to measure time, from seconds and minutes to weeks, years, and decades.

Also known as: time period, duration units

What You Need to Know

Time units are the building blocks we use to measure life and events.

Core units:

  • Second: the base unit of time (60 seconds = 1 minute)
  • Minute: 60 seconds
  • Hour: 60 minutes (3,600 seconds)
  • Day: 24 hours
  • Week: 7 days
  • Month: 28‑31 days depending on the calendar month
  • Year: 365 days (366 in leap years)

Human-scale markers:

  • Decade (10 years)
  • Generation (~25-30 years)
  • Century (100 years)
  • Millennium (1,000 years)

These units help us understand age milestones, calendars, and biological rhythms (heartbeats, breaths, sleep cycles).

Sources & References

This information is sourced from authoritative government and academic institutions:

Put your knowledge into action with these interactive tools:

Time Units Calculator: Life in Days, Weeks, Months