Method

One moment, many local clocks.

Timefold compares absolute instants, then formats each one in the chosen city.

Instants and local time

An instant is a single point on the global timeline. A local time is how that instant appears under a city’s UTC offset and daylight-saving rules.

Working overlap

The green band marks 09:00–17:00 in each city. Timefold highlights moments that fall inside every selected band.

Daylight saving time

Calendar days are not always 24 hours long. A spring transition can create a 23-hour day; an autumn transition can create a 25-hour day. The timeline is built from local midnights, so both cases remain accurate.