Time zone conversion without DST mistakes

How it works

The browser time zone database maps an IANA zone name and a date to an offset. This tool interprets the input in the chosen source zone, converts it to an absolute instant, then formats that instant in the target zone including its own daylight-saving rules.

• Zones are IANA names such as Europe/Berlin or America/New_York; daylight saving is handled by the browser.

Why it matters

Every remote meeting, deployment window and travel booking crosses zones. The expensive mistakes are predictable: a fixed offset used in June, a date that changes across the dateline, or a server formatting in its own default zone.

A worked example

A 09:00 meeting in Berlin on 30 October 2026 is 04:00 in New York and 20:00 in Auckland. In July the same Berlin time would be 03:00 in New York because both sides observe DST differently.

Common mistakes

• Using fixed UTC offsets instead of IANA zone names.
• Converting on the server with its own default zone.
• Ignoring that the date can change across zones.

Practical tips

Share times as an instant plus a zone name, never as a bare local time — "09:00 Europe/Berlin" is unambiguous. When scheduling across regions, check the week of the meeting rather than assuming the offset you used last month still holds.

How to use it

1. Open the tool. Everything runs in your browser tab.
2. Paste or type your input, then choose the action you need.
3. Check the result and copy it with one click.

Open the tool

Common questions