Time Zone Converter
Convert a date and time between cities using the browser's own IANA time-zone database — daylight saving applied automatically, day changes flagged, and every world clock in one table.
Reading a UTC offset
UTC+4 means the local clock reads four hours ahead of Coordinated Universal Time: when it is 12:00 UTC it is 16:00 in Baku. Offsets are properties of a moment, not of a place — New York is UTC−5 in winter and UTC−4 in summer — which is why storing times as UTC (or as a Unix timestamp) and converting at the edges is the only arrangement that survives the year. The unix timestamp converter next door handles that representation.
Everything runs locally in your browser and works offline once loaded.
Frequently asked questions
Where does the time-zone data come from?
From your own browser, which ships the IANA time-zone database — the same dataset operating systems, phones and airlines use. Nothing is looked up on a server, and updates arrive with normal browser updates whenever a government moves its clocks. That is also why the page works offline.
Is daylight saving time handled automatically?
Yes — the offset is computed for the specific instant you entered, not from a static table. Convert a July date and New York is UTC−4; convert a January date and it is UTC−5, with no setting to remember. Zones that abolished DST, like Azerbaijan in 2016 or most of Mexico in 2022, are equally handled because the database records history, not just rules.
What does the "+1d" next to a time mean?
The converted time falls on the next calendar day. 23:00 Tuesday in Baku is already 03:00 Wednesday in Tokyo — the badge is there because scheduling mistakes almost never come from the hour, they come from the unnoticed day change.
What happens if I enter a time that doesn't exist, like 02:30 on a spring-forward night?
During a DST spring-forward the wall clock jumps from 02:00 to 03:00 and the times between never happen; in autumn one hour happens twice. This tool resolves a skipped time to the moment just before the jump and an ambiguous time to its first occurrence — deterministic choices, the same ones most calendar software makes.
Why do some zones differ by half an hour or 45 minutes?
Politics, not astronomy. India (UTC+5:30) chose a single national time halfway between its natural eastern and western zones; Iran (+3:30) and Nepal (+5:45) aligned their clocks to their capitals' solar time. The database carries them all, which is why this page does not assume offsets are whole hours.
My city isn't in the list — what do I pick?
Any city that shares its time zone. Ganja and Sumqayit keep Baku time; the whole of Germany, the Netherlands, Sweden and more keep Berlin time; Boston and Miami keep New York time. Time zones are large — the list names one well-known city per zone rather than every city in it.
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