Time Converter

1. 1Type a value into any box — every other unit updates as you type.
2. 2Use the swap button to flip the two headline units.
3. 3Copy any result with the button beside it.
4. 4Adjust the decimal places if you need more or less precision.

Everything up to a week is exact and unambiguous: a minute is 60 seconds, an hour 3,600, a day 86,400, a week 604,800.

Above a week it gets fuzzy, and it is worth being explicit about the choice made here. A year is taken as 365.2425 days — the Gregorian average, which accounts for the leap-year rules — and a month as one twelfth of that, about 30.44 days. That is why converting 1 month to days gives 30.44 rather than a whole number: there is no single correct answer, so the average is used. For real calendar arithmetic on specific dates, use the age calculator instead.

Conversion works by taking your value to a single base unit and then out again, so every pair of units is consistent with every other. Values are calculated at full double precision and only rounded for display, which means round-tripping a number through two conversions returns what you started with.