How this time zone converter works
The converter treats the entered date and time as wall-clock time in the source IANA time zone. It resolves that time to one instant, then formats the same instant in the target time zone.
IANA time zones and daylight saving
Named zones such as America/New_York and Europe/London can change offset by date. This tool uses browser Intl timezone data so daylight saving is based on the selected date where the browser supports the zone.
UTC offsets vs named time zones
Fixed offsets like UTC-05:00 do not describe daylight saving changes. Named IANA zones are used for conversion, while offsets are shown only as supporting detail for the selected date.
What this tool does not include
This tool does not schedule meetings, connect calendars, infer location, promise historical timezone-law precision or provide legal, travel or scheduling advice.
Key terms and assumptionsShort notes about IANA zones, daylight saving, wall-clock input and browser timezone data.
- Wall-clock source time
- The entered datetime is interpreted as local wall-clock time in the selected source time zone.
- IANA zones
- Calculations use named IANA time zones rather than fixed offsets or ambiguous abbreviations.
- Daylight saving
- Offsets are taken from browser Intl timezone data for the selected date.
- DST anomalies
- Skipped local times are blocked. Repeated local times use the earlier occurrence and show a warning.
- General conversion only
- The result is not scheduling, travel, legal or historical timezone advice.
Related calculators and tools
Browse the Date & Time tools hub for related Date & Time tools.
- Meeting Time Planner Enter one proposed meeting time and compare the local time across multiple IANA time zones.
- Countdown Calculator Calculate the time remaining until a target date and time, or show how long ago a past target passed.
- Time Duration Calculator Calculate elapsed time between two times or datetimes, including overnight spans, hours, minutes and decimal hours.
- Date Calculator Add or subtract days, weeks, months and years from a start date with clear month-end handling.
- Date Duration Calculator Calculate calendar days between two dates, with optional end-date inclusion and practical week or calendar breakdowns.
- Unit Converter Convert common length, weight, temperature, area, volume, speed and time units with a focused measurement converter.
FAQs
How does the converter handle daylight saving time?
It uses IANA time zones through supported browser time-zone data, so the selected date determines the offset where the browser supports that zone.
Why not use fixed UTC offsets?
Fixed offsets do not capture daylight saving changes. Named IANA time zones are safer for real locations.
What is an IANA time zone?
It is a time zone identifier such as America/New_York, Europe/London or Pacific/Auckland.
Can the source and target time zones be the same?
Yes. The result matches the source time and explains that no time-zone change was applied.
What happens during daylight saving clock changes?
Some local times can be skipped or repeated. This version blocks skipped local times and warns when a repeated time is detected.
Does this schedule a meeting?
No. It converts one date and time only. Use the Meeting Time Planner for comparing one proposed time across multiple zones.
Does this know every historical timezone law?
No. It relies on browser time-zone data and should not be treated as legal, travel or historical-research authority.