Time Converters

Time measures the progression of events from past to future, and how long those events last. The SI base unit is the second (s), defined since 1967 by the frequency of radiation emitted by caesium-133 atoms — an atomic clock standard accurate to one second in 300 million years. At the short end, nanoseconds and microseconds matter in computing and electronics; at the human scale, minutes, hours, and days govern daily life; at the long end, years, decades, and centuries frame history. Calendar months range from 28 to 31 days, and calendar years contain 365 or 366 days. This converter instead uses a fixed 365-day year and defines a month as one twelfth of that year; decades and centuries are ten and one hundred of these fixed years. These selections convert durations, not intervals between calendar dates.