Time Duration Converter
Convert between milliseconds, seconds, minutes, hours, days, weeks and years.
How many seconds are in a week? How many hours is 90 days? Time-unit arithmetic is simple in principle but tedious in practice, because the multipliers (1000, 60, 60, 24, 7, 365) all differ — a perfect recipe for off-by-a-factor mistakes in billing, scheduling, and programming.
This converter translates any duration between milliseconds, seconds, minutes, hours, days, weeks, 30-day months and 365-day years. It's especially handy for developers converting timeout values in milliseconds, project managers turning working days into weeks, or anyone checking how many minutes a 12-hour flight really is.
How to use Time Duration Converter
- 1
Enter the duration
Type the amount of time to convert.
- 2
Pick the source unit
From milliseconds up to years.
- 3
Pick the target unit
The converted duration updates live.
Features
- Eight units from milliseconds to years
- Instant conversion in both directions
- Useful for programming timeouts, billing periods and schedules
Frequently asked questions
Common mistakes to avoid
- Using 30-day months for calendar calculations where actual month lengths matter.
- Mixing up milliseconds and seconds in code — a 5000 ms timeout is 5 seconds, not 5000.
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