Time Converter
Runs locally in your browser. Nothing leaves your device.Instantly convert durations between seconds, minutes, hours, days, weeks, and explicitly defined month and year units.
Use a comma or period as the decimal separator; do not use thousands separators.
All units
Subsecond units
Everyday units
Calendar-defined durations
How it works
- 1
Enter value and source unit
Enter the time value and choose the source unit from one of the three groups.
- 2
Choose the target unit
Choose the target unit, even from a different group, for example from seconds to years.
- 3
Copy the result or swap units
Copy one or all results, or swap the source and target unit for the next conversion.
Good to know
The time converter converts directly in your browser between everyday units, subsecond units, and calendar-related durations. Since months and years don't have a fixed calendar length, the tool uses clearly labeled average values for this group: 1 average Gregorian month = 30.436875 days, 1 average Gregorian year = 365.2425 days.
Calculation runs locally in the browser. Decade, century, and millennium are based on the average Gregorian year — this tool is not suited for exact calendar dates such as “Easter in 3 years.”
Typical use cases
Convert time spans for planning and everyday use
Convert hours to minutes or days to weeks, for example for project planning, travel times, or deadlines.
Convert technical time values with subsecond units
Convert milliseconds, microseconds, or nanoseconds, for example for programming, measurement, or latency figures.
Approximate long time spans
Convert years to decades or centuries to roughly gauge long time spans — based on the average Gregorian year.
Tips for better results
Understand months and years as approximations
Since months and years don't have a fixed calendar length, the tool uses clearly labeled average values — for exact calendar dates, a calendar tool is the better choice.
Choose the right order of magnitude for subsecond units
Pay attention to whether milli-, micro-, or nanoseconds are meant — confusing them quickly leads to order-of-magnitude errors in technical calculations.
Features
Three unit groups
Everyday units, subsecond units, and calendar-related durations are cleanly separated.
Local conversion
Calculation happens directly in the browser, without transmission to a server.
Transparent calendar definitions
Month, year, decade, century, and millennium are based on clearly stated average values.
Frequently asked questions
How long is a month in this tool?
A month equals the average Gregorian month of 30.436875 days, since calendar months vary in length.
Is the tool suited for exact calendar dates?
No. Average values are used for calendar-related durations; for exact date calculations, a calendar tool is better suited.
Are my inputs uploaded?
No. Conversion runs entirely locally in the browser.
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