About this tool
Turn a raw number of seconds into a tidy duration like 2d 3h 4m 5s, and convert a duration string back to total seconds, all in your browser.
Frequently asked questions
What duration format does it accept?
A string like 2d 3h 4m 5s using d, h, m and s — any units may be omitted, and a plain number is read as seconds.
How long is a day here?
A day is treated as exactly 24 hours and an hour as 60 minutes, with no calendar or daylight-saving adjustments.