Time Zone Converter

Convert a date and time from one IANA time zone to another with UTC offset, abbreviation, DST notes, day-difference indicator, and a multi-city world clock preview. Search cities such as London, New York, Dubai, Karachi, Tokyo, and Sydney; swap zones; save favorites and recent pairs in browser storage. Calculations run locally — no server upload of your schedule.

How to Use the Time Zone Converter

Pick a source date and time, choose From and To IANA time zones, convert, then read the converted clock time, UTC offsets, DST note, day difference, and world clock preview.

  1. Set the Date and Time for the instant you want to convert (defaults to now).
  2. Search or select the From time zone (source city/region).
  3. Search or select the To time zone (destination city/region).
  4. Optional — tap a favorite or recent zone chip, or use Swap to reverse direction.
  5. Press Convert to see converted time, offsets, DST note, day difference, and world clock preview.
  6. Copy the result from the toolbar or reset to start a new conversion.

IANA zones and DST

The tool uses IANA time zone databases bundled in the browser/runtime. Offsets and abbreviations apply to the exact date-time you enter, including daylight saving transitions. Always confirm critical flight or broadcast schedules with official sources.

Worked examples

  • 3:00 PM Asia/Karachi on 2026-08-02 → America/New_York with day difference shown.
  • Swap London ↔ Dubai to compare meeting times both directions.
  • Use world clock preview to see Tokyo and Sydney at the same instant.

Common mistakes

  • Forgetting that day difference can be −1, 0, or +1 across zones.
  • Using city nicknames instead of selecting the correct IANA zone (e.g. multiple US Central cities).
  • Assuming DST rules never change — governments occasionally adjust policy.

Privacy

Date, time, and zone selections are processed locally. Favorites and recent zones are stored in browser local storage only.

Limitations

Reference converter for planning — not aviation, maritime, or legal timestamp authority. Historical rule changes before your runtime data may edge-case very old dates.

FAQ

How is daylight saving time handled?

Offsets are computed for the exact date and time you enter using IANA time zone identifiers, so DST transitions are reflected automatically for that instant.

What does day difference mean?

Day difference shows whether the target calendar date is before, the same as, or after the source date when the instant crosses midnight between zones.

Can I swap From and To zones?

Yes. Use Swap to exchange the From and To selectors without retyping your search.

How do favorites and recent zones work?

Star a destination zone to pin it as a quick chip. Recent zones from your last conversions appear as shortcuts. Both lists are stored in your browser only.

What is the world clock preview?

After conversion, the tool shows additional city times for the same instant so you can compare several hubs without running multiple conversions.

Which time zones are supported?

Any valid IANA zone such as America/New_York or Asia/Karachi. Use the search box to filter by city or region name.

Does my date/time leave my device?

No. Conversion runs entirely in your browser using local time zone rules. Nothing is uploaded to ToolsLibrary servers.

Can I plan a future meeting across zones?

Yes. Set the date and time to the planned meeting instant, pick source and destination zones, and read the converted local time plus day difference before sending invites.