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What Is the Time Zone Converter?

The time zone converter lets you enter a date and time in one time zone and instantly see what that moment looks like in multiple other time zones simultaneously. It supports 20 major world time zones, shows the current UTC offset and DST abbreviation for each zone, and highlights when the converted date falls on a different calendar day than the source.

How to Use the Time Zone Converter

1. Select your source time zone from the dropdown (e.g., New York).
2. Enter the date and time in that zone, or click Now to use the current time.
3. The results table shows the equivalent time in all selected target zones, with UTC offsets and DST abbreviations.
4. Use the timezone picker at the bottom to add or remove zones from the comparison.

Features

• 20 pre-configured world time zones across all continents
• Automatic DST handling via the IANA time zone database
• Displays UTC offset and DST abbreviation (e.g., PST, CEST) for each zone
• Day boundary indicator (+1 / -1 day) when dates differ from the source
• Toggle-select which zones to display
• "Now" button to set the source time to the current moment

FAQ

How does the time zone converter work?

You pick a source time zone and enter a date and time. The converter interprets that moment in the source zone and displays the equivalent time in each selected target zone using the browser's built-in Intl.DateTimeFormat API, which applies correct DST rules automatically.

Does it account for Daylight Saving Time (DST)?

Yes. The Intl.DateTimeFormat API uses the full IANA time zone database, which includes all historical and current DST transition rules for every supported time zone.

What does the +1 day / -1 day indicator mean?

When the calendar date in a target time zone differs from the source zone's date, the converter shows +1 day or -1 day. This is common when comparing time zones on opposite sides of the UTC±12 boundary.