Time Unit Converter

Which time units does the converter include?

Nanoseconds, microseconds, milliseconds, seconds, minutes, hours, days, weeks, months and years. The second is the base, so every pair is converted exactly as a ratio of seconds.

How long is a month and a year in this tool?

A month is fixed at 30 days (2,592,000 seconds) and a year at 365 days (31,536,000 seconds). Real calendar months run from 28 to 31 days, and the average Gregorian year is 365.2425 days, so these two units are approximations for planning, not calendar arithmetic.

Why does 1 year not equal 12 of the tool’s months?

Because 12 months of 30 days is 360 days, while a year here is 365 days. The converter reflects that: 1 yr is 12.16666667 mo. If you need exact months between two dates, use a date difference calculator instead.

How is the second defined?

The SI second is defined from the caesium-133 atom: it is the duration of 9,192,631,770 periods of the radiation tied to the transition between the two hyperfine levels of its ground state. A minute is 60 s, an hour is 3,600 s and a day is 86,400 s.

Does it account for leap years, leap seconds or daylight saving?

No. A day is always 86,400 seconds, and a year is always 365 days. Leap years, leap seconds, time zones and daylight saving changes are calendar questions, not unit conversions, and are outside this tool.

What are the sub-second units useful for?

Milliseconds describe page load times and audio latency, microseconds describe processor and sensor timing, and nanoseconds describe memory access and signal travel. Each is a thousandth of the one above, so 500 ms is 0.5 s and 1,000,000 μs is 1 s.

Can I convert decimal hours like 1.75 hours to minutes?

Yes, any decimal works: 1.75 hr is 105 min. The result stays decimal, so 2.5 hr is 150 min and 90 min is 1.5 hr. A clock-style answer such as 1 h 45 min must be read from the decimal part yourself.