ISO-8601 Duration Format in a Nutshell

ISO-8601 Duration Format

ISO-8601 standardizes how we represent durations in a compact, unambiguous way. The basic structure for durations is:

P[n]Y[n]M[n]DT[n]H[n]M[n]S

Breakdown:

  • P: Marks the start of the duration period.
  • [n]Y: Number of years.
  • [n]M: Number of months (before the T separator).
  • [n]W: Number of weeks.
  • [n]D: Number of days.
  • T: Separates the date components from the time components.
  • [n]H: Number of hours.
  • [n]M: Number of minutes (after T, M now means minutes).
  • [n]S: Number of seconds.

Quick Examples:

  • PT30M
    • P + T indicates a time duration.
    • 30M means 30 minutes.
  • P1DT2H
    • 1 day and 2 hours.
  • PT15M30S
    • 15 minutes and 30 seconds.

This concise notation is widely used in various frameworks (like ShedLock) and systems to ensure clarity and consistency when specifying time durations.