Time Utilities

Duration Converter

Convert between seconds/milliseconds and days, hours, minutes, seconds.

What is Duration Calculator?

Duration calculator converts between different time units and calculates time spans.

Supported Units

  • Milliseconds, Seconds, Minutes
  • Hours, Days, Weeks
  • Months, Years

Use Cases

  • Time estimation
  • Performance measurement
  • Scheduling calculations

Frequently Asked Questions

Duration versus date difference — what is the distinction?
A date difference answers "how many days from March 1 to March 5" (calendar-aware: unequal months, DST shifts); a duration answers "how many seconds in 2h45m" (pure time quantity). Video lengths, task times, and audio durations belong to the duration tool.
Is an hour always 3600 seconds?
In standard duration math, yes, always. In real calendars, DST transition days can drop or repeat an hour. Use fixed conversion for timing and metrics; bring calendars and timezones in only when scheduling events.
Milliseconds, microseconds, nanoseconds — when does each matter?
Each step is ×1000: 1 s = 10³ ms = 10⁶ µs = 10⁹ ns. Frontend performance lives in milliseconds (100 ms interaction budget), database queries in ms-to-µs, only trading systems and hardware reach nanoseconds. Report metrics in one consistent unit to avoid "0.05 s or 50 ms" confusion.