Time converter
Convert between milliseconds, seconds, minutes, hours, days, weeks, months, years and centuries, then watch a clock sweep and count what happens in that time.
That's about the same as a movie. In that time your heart beats 8,401 times and light travels 2.159×10⁹ km.
What it means
How long is that?
A month here is a year divided by 12 (30.44 days) and a year is 365.25 days, so long conversions stay consistent.
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Your duration in every unit
Learn
Three things worth knowing
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The 3.15 trick
A year is close to 31.5 million seconds, or π×10⁷ to within half a percent. Physicists use that to estimate yearly totals in their heads.
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Why 60 and not 100
Babylonian astronomers counted in sixties because 60 divides by 2, 3, 4, 5, 6, 10, 12, 15, 20 and 30. Splitting an hour into thirds stays whole; a decimal hour would not.
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A month is not 30 days
Months run from 28 to 31 days, so converters have to pick an average. Interest, subscriptions and salaries each use a different convention, which is where billing disputes begin.
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Background
About time units
Time is the one quantity the whole world already agrees on, but it is not decimal. Sixty seconds make a minute and sixty minutes an hour, inherited from Babylonian counting in sixties.
The second is the SI base unit, defined by 9,192,631,770 oscillations of a caesium atom. Days, months and years are astronomy, which is why they refuse to divide neatly.