Time zone converter
Pick two places, a time and a date, and get the conversion with daylight saving already handled. The day strip underneath shows every hour side by side, meeting window tinted.
Guide
How to use it
- Choose the from and to locations, the list covers the major zones by city name.
- Set the time and, importantly, the date: DST means the gap between two places changes through the year.
- Read the conversion, a next-day or previous-day marker appears when the clock crosses midnight.
- Scan the strip for tinted hours, those are 9:00 to 17:59 in both places, the honest meeting window. Tap any hour to convert it.
Examples
Conversions with consequences
Usually 09:00, but for a fortnight each spring and autumn it is 10:00, the US and UK change their clocks on different dates. The date field exists because of exactly this.
London to Sydney is 9, 10 or 11 hours apart depending on the season, both hemispheres shift oppositely. The strip shows the brutal truth: the shared window is roughly 08:00-10:00 London.
Mumbai runs at UTC+5:30, half-hour offsets are real (Adelaide too). The converter renders them exactly, mental arithmetic reliably does not.
Method
How it works
Conversions use your browser’s built-in IANA time zone database via the Intl API, the same rules operating systems use, including every DST transition, half-hour zone and historical quirk. Nothing is approximated from fixed offsets.
The day strip converts each hour of the from-day individually, so a DST switch mid-day renders truthfully. Working hours are taken as 9:00 to 17:59 in each place for the tinting.
FAQ
Frequently asked questions
Why does the gap between two cities change?
Daylight saving starts and ends on different dates in different countries (and not at all in some). For a few weeks each year the usual gap stretches or shrinks by an hour.
Is GMT the same as London time?
Only in winter. Summer London runs on BST (UTC+1). "GMT" in casual use often means "UK time", in aviation and computing it means UTC, this tool’s UTC entry is the unambiguous one.
What about places without DST?
Plenty: India, China, Japan, most of Africa, Arizona. The database knows, which is why picking cities beats remembering offsets.
Which time goes in a calendar invite?
Calendars store instants and render per attendee, so invite in your own zone and let software translate. This converter is for the human conversation before the invite.
Does the tool handle the date line?
Yes: Auckland on a Friday morning is still Thursday in Los Angeles, the day marker in the result says so explicitly.
Is my location tracked?
No. The zone list is fixed, the maths is local, and nothing about your choices leaves the page.
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