Convert Hours to Seconds

About converting Hours to Seconds

Hours (h) and Seconds (s) are both units of time, so converting between them is a single multiplication: multiply your Hours figure by 3,600. Ten Hours comes to 36,000 Seconds, and a hundred works out at 360,000 Seconds.

Rule of thumb: going from Hours to Seconds multiplies, so the figure always grows — one Hour is already 3,600 Seconds. If your answer came out smaller, you have the conversion the wrong way round.

What is a Hour?

An hour is sixty minutes, and the twenty-four-hour day it divides comes from ancient Egypt, though the sixty inside it is Babylonian. For most of history hours were not equal: daylight was split into twelve parts and the night into twelve more, so an hour was simply longer in summer than in winter. Only mechanical clocks made fixed hours practical, since a clock cannot easily be told to run slower in December. The hour is not an SI unit but is accepted for use with SI, and it remains the unit almost all paid work is priced in.

What is a Second?

The second is the SI base unit of time and the reference every other unit here is measured against. It was originally 1/86,400 of a mean solar day, but the Earth’s rotation is not steady enough to serve as a clock, so since 1967 the second has been defined by the caesium-133 atom: 9,192,631,770 periods of a specific hyperfine transition. Atomic time and Earth time therefore drift apart, which is why leap seconds are occasionally inserted to realign them — a fiddly practice that in 2022 was agreed to be phased out by 2035.

To put both in perspective: an hour is a standard slot in most people’s calendars, while a human heartbeat takes about a second.

The converter above updates as you type, and the table lists common values for quick reference. Need the opposite direction? Use the Seconds to Hours converter, or browse all Time converters.