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Time-units converter

Unit converters

Convert nanoseconds, milliseconds, days, weeks, years — durations in every unit.

Updated

Convert time

In every unit

UnitValueCopy
Nanosecond
ns
999,999,999.9999999
Microsecond
µs
1,000,000
Millisecond
ms
1,000
Second
s
1
Minute
min
0.01666667
Hour
hr
0.00027778
Day
day
1.157407e-5
Week
wk
1.653439e-6
Month (avg)
mo
3.802649e-7
Year (avg)
yr
3.168874e-8

Quick start

How to convert time durations

Type a duration, pick the source unit, read the value in every other unit.

  1. Step 1
    Type the value

    Enter the duration and pick its unit. Switching units converts the displayed value so the meaning is preserved.

  2. Step 2
    Read every unit

    Ten units — ns through years — update live. The source unit is highlighted.

  3. Step 3
    Copy the value

    Click Copy on any row to grab the converted value. Everything runs locally — no upload.

In-depth guide

Time-units converter — nanoseconds to years

Convert durations between ten units — from nanoseconds to average Gregorian years. Type a value, pick its unit, every other unit updates live.

For converting epoch timestamps to readable dates, see /tools/epoch-converter instead.

Supported units

UnitSymbolIn seconds
Nanosecondns0.000 000 001
Microsecondµs0.000 001
Millisecondms0.001
Seconds1
Minutemin60
Hourhr3 600
Dayday86 400
Weekwk604 800
Month (avg)mo2 629 746
Year (avg)yr31 556 952

Calendar months vs duration months

This tool treats time as elapsed duration, not as calendar arithmetic. Adding "one month" to a date in software needs calendar-aware logic (the answer for 31 Jan + 1 month is 27 Feb in non-leap years, but elapsed seconds would land you on 2 Mar). The averaged month (~30.44 days) used here is appropriate for capacity planning, log-retention windows, billing-cycle estimates and astronomical contexts — not for absolute date arithmetic.

Conversions worth remembering

  • 1 day = 86 400 s = 1 440 min = 24 hr
  • 1 week = 604 800 s = 168 hr
  • 1 year ≈ 31.56 million seconds ≈ 8 766 hours
  • 1 µs = 1 000 ns; 1 ms = 1 000 µs; 1 s = 1 000 ms
  • 1 day ≈ 86.4 × 10⁹ ns (handy for nanosecond-precision benchmarks)

When to use it vs alternatives

Use this converter when you need a quick value across metric, imperial, data, time, or other unit systems. Use domain-specific engineering, lab, or compliance software when tolerances, significant figures, or standards must be formally controlled.

Common pitfalls

  • Confirm the source unit before copying a result, especially when labels are similar across systems.
  • Rounding can matter for materials, shipping, science, and engineering calculations.
  • Check whether your context expects SI, IEC, US customary, imperial, or regional units.

Privacy and security

Browser-first by design. The tool page explains any exception before you use it.

Your conversion values stay in the browser and update locally as you type. EpitomeTool does not upload source values, copied results, or unit choices to a server.

Frequently asked questions

How long is a 'month' here?

An average Gregorian month: 1/12 of an average year ≈ 30.437 days ≈ 2 629 746 seconds. Calendar months range from 28 to 31 days, so for billing periods or scheduling, calculate against the specific month. Use this converter for back-of-envelope estimates only.

How long is a 'year' here?

The average Gregorian year: 365.2425 days = 31 556 952 seconds. This averages over the leap-year pattern (97 leap years per 400 years). For exact astronomical calculations, the tropical year (365.24219 days) and sidereal year (365.25636 days) differ at the 5th decimal — outside this tool's precision.

Why aren't 'fortnight' or 'decade' included?

They're trivially expressible: a fortnight = 2 weeks, a decade = 10 years. The supported list aims at units that programmers, scientists and project planners actually use in calculations.

Does this handle leap seconds?

No. Leap seconds (rare adjustments to UTC, last added in 2016) are not modelled. For systems that need leap-second-aware durations, use a TAI-based time library.

I'm trying to convert between epoch timestamps — wrong tool?

Yes — for date conversion (e.g. Unix seconds → ISO string), use /tools/epoch-converter. This page converts durations (how much time has passed), not absolute moments in time.

Does the converter work offline?

Yes. Everything runs in your browser. No request leaves the page during conversion.

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