Pick a moment, pick two places, and see the exact same moment in both — with today’s UTC offsets, daylight saving already handled, and a live clock for each side.
Every place on Earth keeps its clock as an offset from UTC, and that offset is not fixed: it jumps when daylight saving starts and ends — on different dates in different countries, and in the opposite season in the southern hemisphere. This converter never guesses an offset. It asks the IANA time-zone database built into your browser (the same database phones and computers use to set their clocks) what each zone’s offset is at the exact moment you picked, converts through UTC, and formats the result in the destination zone.
That is why a January conversion and a July conversion between the same two cities can legitimately give different answers — and why the page always shows each side’s UTC offset next to its time, so you can see which offset was used.
The live difference, a 24-hour comparison table and a preset converter for the busiest route.
Free — try itDifference today, the DST change in summer, and an hour-by-hour table.
Free — try itLive clocks and the full-day comparison for London and Karachi.
Free — try itOne shift in, exact hours and gross pay out.
Free — try itBecause at least one of the two zones usually changes its offset for daylight saving, and the zones rarely change on the same date. New York moves on the second Sunday of March; London not until the last Sunday of March — so for about three weeks the New York–London difference is 4 hours instead of the usual 5. This converter always uses the offset in force on the date you picked.
It is how far that place’s clock sits from Coordinated Universal Time at that moment. New York in winter is UTC−5 (five hours behind UTC); London in summer is UTC+1 (one hour ahead). The difference between any two places is just their two offsets subtracted.
Live rules, not fixed numbers: the page uses the IANA time-zone database shipped inside your browser, which carries each zone’s current rules and history — including southern-hemisphere seasons and zones that abolished daylight saving.
Yes — pick any date. Historical offsets are in the same database, so a conversion for last year uses last year’s rules, which occasionally differ from today’s.
Abbreviations like EST are ambiguous — EST is a fixed winter offset, while “New York time” follows the city’s real rules all year. Choosing the city (its IANA zone) gives the correct answer in every month, which is why this converter lists places, not abbreviations.
All time-zone conversion is one journey through UTC:
Convert 9:00 AM on 15 January 2026 in New York to London. New York’s offset that day is UTC−5, so the moment is 9:00 + 5 = 14:00 UTC. London’s offset in January is UTC+0, so London reads 2:00 PM — five hours ahead. Repeat it for 15 July 2026: New York is on daylight time (UTC−4), so the moment is 13:00 UTC — and London, on British Summer Time (UTC+1), reads 2:00 PM again. Same wall-clock answer, still a 5-hour difference, because both cities moved by an hour. The interesting case is 15 March 2026: New York has sprung forward but London has not, so 9:00 AM in New York is 13:00 UTC and London, still on UTC+0, reads 1:00 PM — the difference shrinks to 4 hours for about three weeks. The converter above reproduces all three answers exactly.
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