Time Zone Converter
Convert a date and time between any world time zones including DST, show UTC offsets, and compare world cities side by side with live clocks.
Time Zone Converter — interactive calculator, computed instantly in your browser.
Time Zone Conversion: UTC Offsets, DST, and Cross-Zone Scheduling
The Same Instant Across Zones
Key Takeaway: Convert through UTC: source wall time minus its offset gives the instant, then add the target offset. Never subtract one wall clock from another.
Time zone conversion sounds like simple addition, but wall-clock subtraction breaks the moment daylight saving shifts one side of the equation. The reliable method is a two-step anchor: project your source time onto UTC, then project that instant into the target zone using its offset at that exact moment.
1. The Anchor Method
- Step 1: A meeting at 09:00 in Dhaka (UTC+6) anchors to 03:00 UTC
- Step 2: 03:00 UTC in New York (UTC−5 in winter) = 22:00 previous day
- Offsets carry the sign toward east — Kathmandu is UTC+5:45, not +5.75 of an hour
- Never subtract wall times directly: crossing a DST boundary makes the naive difference wrong by an hour
2. Daylight Saving Complications
Zones that observe DST (most of North America, Europe, Australia) change their offset twice a year — spring forward, fall back. That means the same source time converts to different targets in July versus January. New York is UTC−5 in January and UTC−4 in July, so a 09:00 Dhaka meeting lands at 22:00 or 23:00 in New York depending on the season. The calculator evaluates the offset at your chosen date rather than assuming a fixed one, and half a dozen zones (Arizona, most of Asia, Africa) never shift at all.
3. Scheduling Across the Line
- Convert both participants' working hours to UTC and look for overlap — this beats pairwise guesses in three-plus-zone calls
- Watch day shifts: a −5 to +6 jump moves the date forward; confirm which calendar day both sides are agreeing to
- Around March and November DST flips, the overlap window moves by an hour for US/Europe calls — re-check invite times the week of the change
- Use ISO-8601 with offsets (2026-10-05T09:00+06:00) in any automated systems to remove ambiguity entirely
🔗 Global Time & Scheduling Tools
Across-the-meeting scheduling, flight planning, and remote-team coordination all hinge on knowing the offset between zones — daylight saving shifts those offsets twice a year. Explore our ⏱️ Date & Time Hub for more chronological utilities.
Count working days to a deadline or measure elapsed clock time with the companion tools below.
Frequently Asked Questions (Time Zone Converter)
Subtract the source zone's UTC offset from its wall time to get UTC, then add the target zone's offset. Example: 09:00 UTC+6 = 03:00 UTC = 22:00 UTC−5 (previous day). Our calculator performs this anchor step automatically and re-checks the offset for DST.
Practically none for everyday scheduling — UTC replaced GMT as the reference and both read 00:00 at the prime meridian. The difference is that UTC is an atomic-clock standard while GMT is tied to Earth's rotation; UK civil time (BST) shifts even though UTC never does.
One country entered or left daylight saving while the other did not, changing their offset difference by an hour. US DST begins the second Sunday in March and ends the first Sunday in November; EU changes the last Sunday in March and October — so the gap between US and Europe differs for parts of the year.
Yes — India, Pakistan, and Bangladesh are UTC+5:30, Nepal is UTC+5:45, and Australia's Adelaide is UTC+9:30. On the other side, Chatham Islands runs +12:45. Never assume an offset is a whole number of hours.
UTC is the neutral anchor because no country observes DST on it. Rotate inconvenient slots fairly across teammates, or find the overlap of everyone's 09:00–17:00 window expressed in UTC — a five-zone team usually gets a workable 1–2 hour band.