Time Converter (All-in-One)

This time converter converts between seconds, minutes, hours, days, weeks, months, and years simultaneously — useful for productivity tracking, project planning, and everyday calculations. Enter one duration and see it expressed across all seven units at once, instead of chaining several manual multiplications together.

Most of these units are far older than the modern calendar: dividing the hour into 60 minutes and the minute into 60 seconds traces back to Babylonian base-60 (sexagesimal) mathematics, while the 7-day week has roots in ancient Babylonian and Jewish traditions tied to lunar phases, later adopted throughout the Roman Empire. The second itself only became the SI base unit for time in the 20th century, eventually redefined in terms of a fixed number of radiation cycles in a caesium atom rather than any astronomical observation — a definition precise enough for GPS and modern computing.

For calendar-accurate durations between two specific dates — which need to account for leap years and the real number of days in each month — see the Age Calculator or the Date Add/Subtract Calculator, both of which work from real calendar dates rather than fixed unit ratios.

Seconds are the SI base unit for time, so every other unit converts through a fixed multiple of seconds: 60 seconds to a minute, 3,600 to an hour, 86,400 to a day, and so on up through weeks and years. Because none of these ratios involve an offset, converting between any two of them is always a single multiplication or division through seconds.

Months are the one genuinely irregular unit here — calendar months range from 28 to 31 days, so there's no single exact "month" length. This calculator uses an average month derived from a standard 365-day year divided into twelve equal parts (365 ÷ 12 ≈ 30.42 days), which keeps every month-based conversion internally consistent, though it will differ slightly from any one specific calendar month.

Each figure represents the exact same duration, just expressed on a different scale — useful whenever you need to compare or communicate a time span in a more convenient unit. A number that looks unwieldy in seconds (like 2,592,000) often becomes intuitive once converted to a larger unit (30 days, in this case).

For reference: a standard workday is 8 hours (28,800 seconds); a week is 10,080 minutes; a non-leap year is 8,760 hours (365 × 24); and a leap year adds 24 extra hours (8,784 total) that this calculator's fixed 365-day year figure doesn't separately account for.