What is Time Unit Converter?

Time Unit Converter lets you quickly convert between nanoseconds, microseconds, milliseconds, seconds, minutes, hours, days, weeks, months, years, decades, and centuries. Enter a value in any unit and see the equivalent in all other units simultaneously.

The converter works in both directions across twelve units: nanoseconds, microseconds, milliseconds, seconds, minutes, hours, days, weeks, months, years, decades, and centuries. Enter a value in any field and every other field updates instantly. You can choose 2, 4, or 6 significant figures, or full precision, and switch on a 'Show formula' view that prints the conversion factor under each value. Months and years use Gregorian averages (30.44 days per month, 365.2425 days per year), which is what you want for project timelines and salary maths. Need exact calendar math? Switch on 'Specific year' and type a year to size the month, year, decade, and century fields off that year's real length (366 days in a leap year, 365 otherwise).

How to use

1. Enter a numeric value in the input field.
2. Pick the source unit you want to type into — anything from nanoseconds to years.
3. View the converted values across all time units displayed below.

When to use

• Estimating project effort in hours when the deadline is given in weeks.
• Translating sleep, fasting, or training durations between minutes, hours, and days.
• Sanity-checking ping or response times when the spec mentions milliseconds.

Result

A project manager converts 10,000 hours to see it equals about 416.67 days or 1.14 years of continuous time.

FAQ

Why is 1 month not exactly 30 days?

Calendar months are 28 to 31 days long, so the converter uses the Gregorian average of 30.4369 days per month (365.2425 / 12). That gives the closest neutral answer when you're estimating quarters, salary annualisation, or rough timelines without a specific calendar.

What's the year length you use, 365 or 365.25?

The Gregorian year, 365.2425 days. It accounts for the standard leap rule (one extra day every four years, skipping century years not divisible by 400). Over a four-century span it matches the actual calendar precisely, which is what you want for financial or scientific work.

Can I convert decimal hours like 1.5 h?

Yes. Type 1.5 in the hours field and you'll see 90 minutes, 5400 seconds, and 0.0625 days at once. Negative numbers work too, useful for time-zone offsets or showing schedule slippage.

Why does 1 millisecond show as 0.001 second?

Because that's the precise relationship: a millisecond is one thousandth of a second, a microsecond one thousandth of a millisecond, and a nanosecond one thousandth of a microsecond. Switch the precision toggle to keep two or four figures if the small numbers look noisy, or to full if you want every digit.

Is there a way to download the results?

Yes, you can copy every value at once with the 'Copy all' button, or export the current row of all twelve conversions to a CSV file. Useful when you want to log every conversion in a spreadsheet or attach the numbers to a project document.

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