Time Zone Converter — Compare Times Across the World
Convert any time between the world's time zones instantly. Pick a source zone, set a time, and see the corresponding local time in one or several target zones at once — with daylight saving time handled automatically, since the converter uses the official IANA time zone database that tracks every zone's rules and historical changes. A live mode keeps all displayed clocks ticking in real time.
Time zone mistakes are among the most common scheduling errors: a meeting booked for "3 PM" means different instants in New York, London, and São Paulo, and DST transitions shift the offsets between cities twice a year. Converting explicitly before you send an invite, book a call, or catch a live event avoids missed connections — especially across regions that observe DST on different dates or not at all.
How it works
The converter uses the IANA Time Zone Database through the browser's Intl.DateTimeFormat API. Your input time is interpreted as wall-clock time in the source zone and resolved to an absolute UTC instant; that instant is then formatted in each target zone, applying its UTC offset and any daylight saving rule in effect on that date. Because rules are date-dependent, the same pair of cities can differ by different amounts in January and July.
Use cases
- Scheduling meetings and calls with colleagues or clients in other countries
- Converting webinar, launch, and live event times announced in another zone to your local time
- Checking what time it is right now in several cities before messaging someone
- Planning flight arrivals and connections across time zones
- Coordinating deadlines announced in UTC with distributed remote teams
- Finding an overlap window that falls within working hours for every participant
Frequently asked questions
How does a time zone converter work?
It anchors your input to a single absolute instant. The time you enter is interpreted as local wall-clock time in the source zone and converted to UTC; that UTC instant is then rendered in each target zone using its current offset. Offsets come from the IANA time zone database, which encodes every zone's rules, including daylight saving transitions and historical changes.
What is the difference between UTC and GMT?
For everyday purposes they show the same time, but they are defined differently. GMT (Greenwich Mean Time) is a time zone historically based on solar time at the Greenwich meridian, while UTC (Coordinated Universal Time) is the modern scientific standard kept by atomic clocks and adjusted with leap seconds. Time zone offsets and technical systems are defined relative to UTC, which is why you see notations like UTC-3 or UTC+5:30.
How does daylight saving time affect conversions?
DST shifts a zone's UTC offset, typically by one hour, during part of the year — and different regions switch on different dates or not at all. The gap between London and New York, for example, is usually 5 hours but briefly becomes 4 in late March because the US changes clocks before the UK. This converter applies each zone's rules for the specific date you enter, so seasonal shifts are handled automatically.
Why do some time zones have 30 or 45 minute offsets?
Offsets are political choices, not just geography, and several regions picked half-hour or quarter-hour offsets to better match local solar time or for historical reasons. India uses UTC+5:30, Newfoundland UTC-3:30, Iran UTC+3:30, and Nepal UTC+5:45. Converters based on the IANA database handle these fractional offsets exactly like whole-hour ones.
How do I find a good meeting time across several time zones?
Convert a few candidate times into every participant's zone and look for a slot that lands within normal working hours for all of them. For example, 9:00 in Los Angeles is 12:00 in New York, 17:00 in London, and 13:00 in São Paulo (offsets vary slightly with DST) — workable for all four. With participants spread from the Americas to Asia a fully comfortable overlap may not exist, in which case teams usually rotate the inconvenient slot.