CleanorTools
Time

Time Zone Converter

Details

How to use Time Zone Converter

What the tool does, how to run it, and what to expect from the result.

How to convert a time between time zones

The converter takes a wall-clock date and time plus the zone that wall clock belongs to, resolves it to a single instant in time, and then renders that instant in every target zone you have added.

Each target row shows the local date, the local time, and the UTC offset that applies on that specific date, so daylight saving is handled per conversion rather than per city.

  • Type the date and time exactly as it reads on the clock in the source city.
  • Set the source time zone to that city (or to UTC if the time was quoted in UTC).
  • Add each target zone you care about from the dropdown.
  • Read the converted time and the UTC offset on each target row.
  • Click Copy result to put every target on the clipboard as one line per zone.

Why the source zone is the field that matters

A wall-clock time on its own is meaningless: 15:00 is a different instant in Berlin than it is in Chicago. The converter therefore does two steps, not one. It takes your date and time plus the source zone and resolves them into a single moment in time, and only then renders that moment in each target zone. Getting the source wrong shifts every result by the same amount, which is the single most common way to end up an hour off.

The rule is simple: set the source to the city the time was quoted in, not the city you are sitting in. If a colleague says "three my time" and they are in Berlin, set the source to Berlin and type 15:00. When a time arrives already expressed in UTC, set the source to UTC, which is the first option in the list. Coordinating more than three cities is easiest if you quote everything in UTC and convert outward.

  • Source zone defaults to your own detected zone on load.
  • Targets default to New York, London, and Tokyo, and each can be removed.
  • Times are rendered on a 24-hour clock with seconds.

Offsets, abbreviations, and daylight saving

Each target row shows a real UTC offset computed for the instant you are converting, in the form UTC-04:00. That is deliberate, because zone abbreviations are ambiguous and offsets are not. CST means Central Standard Time in North America, China Standard Time in Asia, and Cuba Standard Time in the Caribbean, and IST covers India, Ireland, and Israel. An offset cannot be misread that way.

Because the offset is derived per instant rather than per city, daylight saving falls out automatically. New York reads UTC-05:00 in January and UTC-04:00 in July, and Sydney moves the opposite way, since the southern hemisphere shifts in the other season. A handful of zones use offsets that are not whole hours: India is UTC+05:30 year-round, Nepal UTC+05:45, and parts of Australia use half-hour offsets, all of which are shown as hours and minutes.

Tips

Getting a better result out of Time Zone Converter

Specific settings and thresholds, not general advice.

  • Enter the wall-clock time as it reads on the clock in the source city, then pick that city as the source zone. The converter turns those wall-clock fields into a UTC instant and re-renders it in every target zone, which is the correct mental model and the one people get backwards.
  • The offset shown per target is computed for the converted instant, not for today. Convert a meeting for October and London may read UTC+01:00; convert the same wall time in December and it reads UTC+00:00, because the tool consults the browser's DST rules for that date.
  • There are two wall-clock times each year that do not convert cleanly: the hour that is skipped when clocks spring forward does not exist, and the hour that repeats when they fall back is ambiguous. The tool resolves those by a single offset correction, so it picks one interpretation rather than warning you. Do not schedule anything inside a transition hour.
  • The datetime-local input has minute granularity, not seconds, so there is no way to convert an instant to the second here. For log-timestamp work you want an epoch converter instead.
  • The source zone defaults to your own detected zone but you can set it to any of the 44 listed zones, including UTC. Setting it to UTC and converting outward is the safest habit when you are coordinating across more than three cities.
Limits

What Time Zone Converter does not do

The honest boundary, so you do not lose time finding it yourself.

  • 44 preset IANA zones, no free-text city search.
  • Minute granularity only; no seconds and no epoch timestamp input or output.
  • Ambiguous or nonexistent wall times at DST transitions are resolved silently, with no warning.
  • No meeting planner, no working-hours overlap, and no calendar invite export.
At a glance

Who Time Zone Converter is for

A quick way to understand who this helps, what it solves, and where it connects next.

Best fit

Anyone scheduling across time zones.

Ideal for

Using the time zone converter without installing anything or signing up.

FAQ

Common questions

Short answers for the questions people usually have before trying a utility like this.

Does it handle daylight saving correctly?

For any normal time, yes. The offset for each zone is recomputed for the specific instant you are converting, using the IANA rules that ship with your browser, so a July meeting and a January meeting in the same city convert differently. The one place to be careful is a wall time that falls inside a DST transition, which is either nonexistent or ambiguous by definition.

What happens if I enter a time inside the DST changeover hour?

The converter resolves it by taking a single offset correction, which means it silently picks one of the two possible interpretations rather than asking you. In practice you get a valid result, but it may not be the one you meant. The real fix is not to schedule anything in the hour a country shifts its clocks, which is why airlines and calendars avoid it too.

How do I copy the whole conversion out?

Copy result puts one line per target zone on your clipboard, in the format "New York: Oct 14, 2026 09:30 (UTC-04:00)". That is a paste-ready block for a meeting invite or a Slack message, and it includes the offset so nobody has to guess.

Which zone should I use as the source?

Whichever city the time was quoted in. If a colleague says "3pm my time" and they are in Berlin, set the source zone to Berlin and type 15:00. Converting from your own zone when the time was quoted in theirs is the single most common way to end up an hour off.

Is any of this sent to a server?

No. Both the offset calculation and the formatting use the Intl APIs built into your browser, which include the IANA time-zone database. There is no API call, so the converter also works with the network off.

My city is not in the list. What do I do?

Pick any listed city that shares its offset and daylight-saving rules, and the times will be identical. The picker holds 44 curated zones plus UTC rather than the full IANA database of several hundred, and there is no free-text search, so for an unusual zone choose the nearest listed city that follows the same rules.

Does it show seconds?

The target rows display hours, minutes, and seconds on a 24-hour clock, but the input only accepts hours and minutes, because it is a standard datetime-local field. So you can read a seconds figure, you just cannot set one. For second-level work on log timestamps, an epoch converter is the right tool.

Do my chosen cities stay next time I open the page?

No. The board resets to your detected source zone and the three default targets on every reload. There is no local storage and no account, so nothing about where you are or who you work with is retained between visits.

Is it free?

Yes, free with no signup and no limit on how many target zones you add. Everything is computed by your browser, so there is no quota to hit and no server cost to pass on.

How accurate are the offsets?

As accurate as the time-zone database shipped with your browser and operating system, which is where the IANA rules live. That is normally current, but a very old, unpatched device can carry stale rules for a country that has recently changed its daylight-saving policy, and no page-level tool can correct for that.

Recommendations

You Might Also Like

Nearby tools from the catalog that fit the same job or workflow.

24h
UtilityTime

Military Time Converter

24-hour clock, both directions

Convert 24-hour military time to the 12-hour clock and back, both live.

TIME
UtilityTime

Time Converter

Convert time units

Convert time units like minutes to seconds, hours to minutes instantly in your browser. Free, no upload, no sign-up.

WC
UtilityTime

World Clock

Time

See the current time in cities and time zones worldwide at a glance. Free, in your browser, nothing is uploaded.

UNIX
UtilityUnix

Unix Timestamp Converter

Convert Unix timestamps

Convert Unix seconds or milliseconds into ISO, UTC, and browser-local time.

TC
UtilityTime

Time Calculator

Time

Add or subtract days, hours, minutes and seconds, or measure the gap between two times. Free, in your browser, nothing is uploaded.

SW
UtilityTime

Online Stopwatch

Online stopwatch

Start, pause, and reset a stopwatch that counts up. Free, in your browser, no sign-up.

Cleanor app

Do it all on your device

Cleanor puts these tools in one app: compress and convert images, video, and audio, work with PDFs, and scan text right on your device. Plus free up storage and clear inbox clutter with Email Cleaner. Start with a free trial.

  • iPhone
  • Android
  • Macsoon
  • Windowssoon
Get it on the App StoreGet it on Google PlayAll platforms & pricing