Time Converter

s · min · hr · day · wk · mo · yr · ms · μs

Convert time units instantly between seconds, minutes, hours, days, weeks, months, and years. This free online tool handles both tiny units like nanoseconds and large spans like decades and centuries.

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Quick Reference

  • 1 hr = 3,600 s
  • 1 day = 86,400 s
  • 1 year = 365.25 days = 31,557,600 s

Conversion Table

UnitNameValue

About Time Units

Time is one of the seven SI base quantities, measured in seconds (s). From nanoseconds in electronics to millennia in geology, time spans an enormous range. The second is defined by atomic transitions in caesium-133, making it one of the most precisely defined units in science.

Common Conversions

Everyday life relies on hours, minutes, and seconds. Science and computing often use milliseconds and microseconds, while project management and scheduling use days, weeks, and months. This converter handles all scales in a single tool.

Quick Reference — Key Values

1 Minute
= 60 seconds
1 Hour
= 3,600 s = 60 min
1 Day
= 86,400 s = 24 hr
1 Week
= 604,800 s = 7 days
1 Month (avg)
≈ 2,629,800 s
1 Year (Julian)
= 31,557,600 s
1 ms
= 0.001 s = 1,000 μs
1 μs
= 0.000001 s = 1,000 ns
1 Decade
= 10 years
1 Century
= 100 years

Worked Examples

2.5 Hours to Minutes

Multiply hours by 60.
2.5 × 60 = 150
= 150 minutes

1,000 Seconds to Minutes

Divide seconds by 60.
1,000 ÷ 60 = 16.6667
= 16.667 minutes

30 Days to Hours

Multiply days by 24.
30 × 24 = 720
= 720 hours

1 Year to Seconds

1 Julian year = 365.25 days.
365.25 × 86,400 = 31,557,600
= 31,557,600 seconds

When You Need This Converter

Programming & Dev

Convert API timeout values, cache TTLs, and timestamps between ms, seconds, and hours.

Sports Timing

Convert race times from milliseconds to minutes:seconds or compare lap times across units.

Astronomy

Work with light-travel times, orbital periods, and stellar ages spanning seconds to centuries.

Project Management

Convert sprint durations, deadlines, and estimates between days, weeks, and hours.

Cooking & Recipes

Scale cooking times — convert minutes to hours or break down long slow-cook periods.

Finance & Interest

Calculate daily interest, annualize rates, or convert loan terms between months and years.

Mental Math Tips

Hours to Seconds

Multiply hours by 3,600 (= 60 × 60). Quick check: 2 hr = 7,200 s.

Days to Hours

Multiply days by 24. A week = 7 × 24 = 168 hours.

Years to Days (approx)

Multiply years by 365 for a quick estimate. For precision, use 365.25 days/year.

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Frequently Asked Questions — Time Converter

There are 86,400 seconds in a day. This is calculated as 24 hours × 60 minutes × 60 seconds = 86,400 s.
A Julian year has 8,765.82 hours (365.25 days × 24). A common calendar year has 8,760 hours (365 × 24).
A regular year has 52 weeks and 1 day (52.1786 weeks). A leap year has 52 weeks and 2 days (52.2857 weeks).
Divide the millisecond value by 1,000. For example, 500 ms ÷ 1,000 = 0.5 seconds. This tool does it automatically.
A leap year has 366 days instead of 365, adding 86,400 extra seconds. This tool uses the Julian year (365.25 days) for year conversions to account for leap years on average.
A Unix timestamp counts the number of seconds elapsed since January 1, 1970 (UTC). It’s widely used in programming and databases to represent dates and times as a single integer.
An average month has approximately 2,629,800 seconds (30.4375 days × 86,400). Exact values range from 2,419,200 s (February in a non-leap year) to 2,678,400 s (31-day months).

All Time Conversions

Common
s → minmin → smin → hh → minh → dd → hd → wkwk → d
Small Units
ms → ss → msμs → msms → μsns → μsμs → nss → μsms → min
Large Units
d → momo → dmo → yryr → mod → yryr → dwk → mowk → yryr → decadedecade → yryr → century
Work & Study
min → hh → minh → dd → hmin → ds → hh → wkwk → h