Time Zone Converter
Convert a date and time in one zone to several others at once, with daylight saving applied for that date, offsets shown and working hours marked.
Free · No sign-up · Your inputs stay in your browser
Input
Convert a time between time zones
Output
Converting…
Converted with the IANA time zone database in your browser, so daylight saving is applied for the date chosen, not today. Store instants in UTC and convert at the edge; store the zone name (Europe/Berlin), not an offset, for future events, because offsets change when governments change the rules.
Runs in this browser. Nothing you paste is sent to a server.
About this tool
Method, assumptions, practical next steps, and limits.
Store instants, display zones
A timestamp in UTC identifies a moment; a zone name such as Europe/Berlin says how to display it. Store the first and convert at the edge. For events in the future, store the wall time and the zone name instead of an offset, because governments change daylight saving rules and an offset computed today can be wrong next year. The zone data comes from the IANA time zone database, which browsers, PHP and PostgreSQL all use.
The awkward hours
When clocks go forward, an hour of wall time does not exist; when they go back, an hour happens twice. A job scheduled at 02:30 local time can run twice or not at all on those nights, which is one reason to run servers and cron in UTC.