Home/Converters/Time zone converter
ConverterTime Zone Converter
Pick a date, a time, and the zone it's in — see it converted everywhere else at once. Runs on the browser's own IANA time zone database, the same source every operating system uses.
Coordinated Universal Time
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| Zone | Local time | UTC offset |
|---|
Two kinds of local time that trip up every converter
Time zones are not fixed offsets — they are rules that change twice a year in most of the world, and the moment of change creates two situations a naive converter gets wrong.
The spring-forward gap. When clocks jump forward — say from 01:59 straight to 03:00 — every local time between 02:00 and 02:59 simply never happens that day. If you ask this converter for 02:30 on a spring-forward date, that instant does not exist in that zone; it will tell you so rather than silently picking a nearby time and pretending it is correct.
The fall-back overlap. When clocks fall back — say from 01:59 to 01:00 — every local time between 01:00 and 01:59 happens twice: once before the change, once after. "01:30" on that date is genuinely ambiguous without also knowing whether it is the first or second time round. This converter flags the ambiguity and tells you which of the two instants it picked.
Both cases are a direct result of DST rules being political decisions, not physical ones — a government can move the transition date, shorten it, or abolish it entirely, and several have. The IANA database this tool reads from is updated for exactly that reason, several times a year.
Not every zone is a whole number of hours from UTC
It is easy to assume every offset is a clean number of hours. A handful of countries deliberately chose otherwise, usually to sit between two neighbours' time zones rather than fully inside either.
| Zone | Offset | Why |
|---|---|---|
| India (Asia/Kolkata) | +05:30 | A single zone for the whole country, splitting the difference between its eastern and western longitude rather than using two zones |
| Nepal (Asia/Kathmandu) | +05:45 | Set deliberately 15 minutes ahead of India, partly to assert an independent national identity |
| Myanmar (Asia/Yangon) | +06:30 | Half-hour offset, distinct from neighbouring Bangladesh and Thailand |
| Chatham Islands, NZ (Pacific/Chatham) | +12:45 / +13:45 | Forty-five minutes ahead of mainland New Zealand, and it still observes its own DST on top of that |
None of these are converter quirks — they are the legally defined offset for that place, and treating them as "close enough" to the nearest whole hour will misreport the actual local time by up to forty-five minutes.
Why this can't be solved with a fixed offset table
A static "UTC+X" list goes stale twice a year for anywhere that observes daylight saving, and permanently the day a government changes its rules. This converter instead asks the browser's own Intl.DateTimeFormat API, with a timeZone option, to do the lookup against the IANA tz database bundled with the browser — the same database your phone, your laptop and most servers already keep updated. There is no separate offset table in this page to go out of date.
Questions people ask
What happens if I enter a time that does not exist?
The converter tells you plainly, in the message area above the results, that the local time falls in a spring-forward gap for the zone you selected, and shows the nearest instant it used instead.
How does it pick which of the two "fall-back" times you meant?
When a local time is ambiguous, the converter resolves it to one specific UTC instant and states both possible offsets in the warning message, so you can tell if it picked the one you meant. There is no way to remove the ambiguity from the input alone — the 24-hour clock genuinely does not carry enough information to distinguish the two occurrences.
Does this tool know about future law changes to time zones?
Only as far as the browser's built-in tz database has already been updated for them. Governments sometimes announce DST changes shortly before they take effect; if your browser has not been updated since, this converter will not know either.