What units does the human format accept?

Days (d/day), hours (h/hr/hour), minutes (m/min/minute), seconds (s/sec/second), and milliseconds (ms). Plurals work. Order doesn't matter — "30m 1h" parses fine.

What does a bare number mean?

A bare number (e.g. `90`) is interpreted as seconds. Use `90 min` or `90:00` if you mean minutes.

Does it support negative durations?

Yes — prefix with `-`. Useful for representing offsets like "finishes 5 minutes early".

What ISO 8601 forms are accepted?

The `P[D]T[H][M][S]` shape used in APIs like Google Calendar and YouTube — e.g. PT1H30M, P1DT2H, PT45S. Weeks (W) and the larger years/months are not supported because their length depends on the calendar.

Duration Formatter

Type a duration in any common form — "2d 4h", "90 min", "5400" (seconds), "01:30:00", or ISO 8601 "PT1H30M" — and see every other representation at once. Handy for translating between log formats, API duration strings, video timestamps, and human-readable summaries without doing the math.

—

Duration

Human

1 hour 30 minutes

Short

1h 30m

Clock

1:30:00

ISO 8601

PT1H30M

Seconds

5400 s

Minutes

90 min

Hours

1.5 h

Days

0.0625 d

Calendar-relative units (weeks, months, years) aren't supported — their length depends on the date.

How to use

Type a duration: "1h 30m", "5400", "01:30:00", or "PT1H30M".
Read off the equivalent in every other format.
Copy whichever representation you need.

Frequently asked questions

What units does the human format accept?: Days (d/day), hours (h/hr/hour), minutes (m/min/minute), seconds (s/sec/second), and milliseconds (ms). Plurals work. Order doesn't matter — "30m 1h" parses fine.
What does a bare number mean?: A bare number (e.g. `90`) is interpreted as seconds. Use `90 min` or `90:00` if you mean minutes.
Does it support negative durations?: Yes — prefix with `-`. Useful for representing offsets like "finishes 5 minutes early".
What ISO 8601 forms are accepted?: The `P[D]T[H][M][S]` shape used in APIs like Google Calendar and YouTube — e.g. PT1H30M, P1DT2H, PT45S. Weeks (W) and the larger years/months are not supported because their length depends on the calendar.

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