Time Converter

Instantly convert durations between seconds, minutes, hours, days, weeks, and explicitly defined month and year units.

Duration

From unitTo unit

Result for 1 h in d

Use a comma or period as the decimal separator; do not use thousands separators.

All units

Subsecond units

Picosecond (ps)

3.6e15

Nanosecond (ns)

3.6e12

Microsecond (µs)

3,600,000,000

Millisecond (ms)

3,600,000

Everyday units

Second (s)

3,600

Minute (min)

Hour (h)

From

Day (d)

0.0416667

Week (wk)

0.00595238

Fortnight (fn)

0.00297619

Calendar-defined durations

Month (avg Gregorian) (month (avg))

0.00136895

Quarter (avg) (quarter (avg))

0.000456318

Year (365 days) (year (365 d))

0.000114155

Year (avg Gregorian) (year (avg))

0.000114079

Year (366 days) (year (366 d))

0.000113843

Decade (decade)

0.0000114079

Century (century)

0.00000114079

Millennium (millennium)

1.14079e-7

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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.

Typical searches include hours to minutes, seconds to days, and convert time. 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.

How it works

Step by step

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.

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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