Time Zones Converter
Convert one date-time into every world time zone at the same instant.
Covers 50 time zones, including daylight-saving variants and half-hour offsets.
Updated August 14, 2026
Introduction / overview
Time Zones Converter takes one instant — the date and time you care about — and shows that same instant in 50 different world time zones at once. Type the reference time into the UTC/GMT box and read the local time in New York, London, Tokyo, Sydney, or anywhere else on the list, without working out a single offset by hand.
Every box is editable and every box is the same moment. Type into UTC/GMT, or into any single time zone — Eastern or Western, standard or summer — and the whole grid recalculates by itself. You never have to add or subtract hours on paper.
This is the tool for the small, everyday question: “if it’s 9 a.m. for me, what time is it for them?” Scheduling a call across continents, checking when a colleague in another office logs on, reading a timestamp from an email header, or comparing hours before booking a flight. By default the converter shows the most common zones; tick Display all time zones to bring in the summer-time (daylight-saving) variants and the rarer half-hour and 45-minute zones.
How to use / quick start
Enter the instant you know
Type a date and time into UTC/GMT — or, if you already know a local time, type it into that zone's own box instead. Any one input is enough.
Read the matching zone rows
The Eastern and Western time zone groups fill in the same instant for every zone. If the city you need isn’t shown, tick Display all time zones to reveal the summer-time and additional zones.
Watch the date, not just the time
Some zones land on the previous or next calendar day. That is normal — crossing the International Date Line or midnight changes the date. The converter shows the full date for every zone, so nothing is left to guesswork.
Example — “if it’s 09:00 UTC, what time is it elsewhere?”
Type into the UTC/GMT box. The calculator adds or subtracts each zone's offset to the reference instant:
Note how IDLW (International Date Line West) shows the previous day: subtracting 12 hours from just past midnight rolls back to the 24th. The same reasoning applies in reverse — if you enter a local time instead of UTC, everything else re-derives from it.
Calculation method
Every field in the calculator is the same point in time. Each time zone is defined by a fixed offset from UTC, and the local time is simply the reference instant shifted by that offset:
where is the zone's offset in hours from UTC — positive to the east, negative to the west. Internally the tool works in milliseconds, so the calculation is exact: the offset of for IST is exactly , with no rounding.
Which directions can it solve?
- UTC/GMT → every Eastern and Western zone (the usual direction)
- Any single time zone → UTC and all the other zones
Because each zone is a fixed offset from the same reference, editing any one box simply re-derives the instant everywhere — there is no conflict between rows.
Offsets come in more than whole hours
Most zones are a whole number of hours, but several are not. India sits at (IST), Nepal at (NPT), and Newfoundland at (NST). The converter handles all of them, including the odd 45-minute zone, so UTC becomes in IST and in NPT.
Daylight saving is not automatic
Each row uses a fixed offset, so the standard zone and its summer-time (daylight-saving) variant are listed as separate rows — for example CET versus CEST, or EST versus EDT. The tool never guesses which rule is in effect; you pick the row that matches the date you are converting. Ticking Display all time zones reveals all the summer-time rows.
Dates roll over at the International Date Line
The farthest-east zones (such as IDLE, UTC+12) and farthest-west zones (such as IDLW, UTC−12) can be a full day apart. That is why the converter always shows the complete date — an instant that is December 25 in New Zealand can still be December 24 in Hawaii.
Common scenarios
Scheduling a call across continents
Pick a proposed time and read every participant’s local hour in one glance, instead of adding offsets one by one. You can also type a participant’s local time and let the grid show the rest.
Distributed teams and deadlines
When a team spans New York, London, and Bangalore, a “by end of day” deadline means very different times. Convert one deadline instant to see who is still in the office.
Travel planning
Check what time it will be at your destination before you book, and confirm whether the destination is on standard or summer time on your travel dates.
Reading timestamps stored in UTC
Emails, databases, and APIs often store times in UTC. Drop a UTC timestamp in the reference box to see it in your own zone and in everyone else’s. If you start from a raw epoch number instead, the Unix Time Converter turns the number into a UTC date-time first.
Tips & best practices
Choose the standard or summer row yourself
In the northern summer, New York is on EDT (UTC−4), not EST (UTC−5). If you convert “right now” during daylight saving, pick the summer-time row (shown under Western Summer Time Zones once you tick Display all time zones) or you will be an hour off.
Mind the abbreviations — they collide
“CST” means Central Standard Time in the US, China Standard Time in Asia, and Central Standard Time in Australia. “IST” is both Irish Summer Time and Indian Standard Time. The converter groups several names on one row (for example IRKT/CST/AWST/WST), so read the full label rather than assuming a three-letter code.
Anchor on UTC for clean results
When converting many zones at once, entering the instant in UTC/GMT is usually the least ambiguous starting point, because every other row is defined against it.
Treat the result as an instant, not a trend
The converter answers “what time is it at this exact moment?” It does not track DST transition dates or past changes to a country’s offset. For a future date, use the zone row that matches the rule you expect to be in force.
Frequently asked questions
Why does one of the zones show a different date?
Because the same instant falls on different calendar days on either side of the International Date Line, and anywhere midnight has already passed. If , then IDLW (UTC−12) shows — still the previous day. That is correct, not a rounding slip.
Why are some offsets :30 or :45 instead of a whole hour?
A few countries chose an offset that is not a whole hour so their local time better matches the sun’s position. Examples are IST at , NPT at , and NST at . The converter treats them exactly like any other zone.
Does this converter apply daylight saving automatically?
No. Every row is a fixed offset, so standard zones and their summer-time variants are separate rows — CET vs CEST, EST vs EDT. Choose the row that matches the rule in effect on the date you care about; the tool does not decide for you.
Limitations
Time-zone offsets here are fixed values, so the tool does not apply daylight-saving rules for a given date — you select the standard or summer-time row yourself. Real-world zones also follow political borders that occasionally change, and the abbreviations used here are short labels for a region, not a guarantee that a particular city uses that exact offset today. The converter answers for the fixed offsets it lists; for official current offset rules in a specific place, check a government or standards source. Input is a valid calendar date and time, so dates without a calendar representation are not accepted.
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