Time Unit Converter

Every unit converts to seconds first using fixed, exact definitions (1 minute = 60 s, 1 hour = 3600 s, 1 day = 86400 s, 1 week = 604800 s), then from seconds to the target unit. Converting through a common base unit keeps every conversion pair exact.

This deliberately stops at weeks — months and years don't have a single fixed length in seconds (a month is 28 to 31 days, a year is 365 or 366), so converting to or from them requires an averaging assumption instead of an exact factor. See the Date Difference Calculator for that kind of calendar-aware math.