Convert Years to Weeks

About converting Years to Weeks

Years (yr) and Weeks (wk) are both units of time, so converting between them is a single multiplication: multiply your Years figure by 52.1786. Ten Years comes to 521.7857 Weeks, and a hundred works out at 5,217.86 Weeks.

Rule of thumb: going from Years to Weeks multiplies, so the figure always grows — one Year is already 52.1786 Weeks. If your answer came out smaller, you have the conversion the wrong way round.

What is a Year?

There is no single year. A Julian year is exactly 365.25 days; a Gregorian calendar year averages 365.2425 days, because its leap rule drops three leap days every four centuries; and the tropical year — the actual round trip of the seasons — is about 365.2422 days. The leap-year rules exist precisely to stop the calendar drifting away from that tropical figure. This converter uses the Julian year of 31,557,600 seconds, the convention astronomers use and the one the light-year is built on, but it is a chosen convention rather than a fact about the Earth.

What is a Week?

The week is the odd one out among common time units: the day, the month and the year all have something astronomical behind them, but seven days answers to nothing in the sky. It is a cultural and religious convention that happened to spread worldwide, and it divides evenly into neither a month nor a year, which is why calendars never repeat neatly. Because businesses still need to agree on what "week 32" means, ISO 8601 defines a week-numbering system: weeks start on Monday, and week 1 is the one containing the first Thursday of the year.

To put both in perspective: a year is one lap of the Earth around the Sun, while a week is the gap between one Monday and the next.

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