How calculations work

Calendar calculations use real month lengths and leap years rather than treating every month as a fixed number of days. Pure dates are handled independently of your device time zone.

Business days

Business-day results count Monday through Friday and exclude weekends. They do not exclude public holidays because those differ by location and can change.

Time zones

Time-zone conversions use the IANA time-zone information built into your browser, including known daylight-saving rules. Results can depend on how recently your browser or operating system was updated.

Timers

Countdowns and stopwatches use the browser clock. A sleeping device or heavily restricted background tab can delay visible updates, although the stopwatch recalculates elapsed time from the underlying clock.