Time Zone Converter

How time-zone conversion works

Every time zone is defined by its offset from Coordinated Universal Time (UTC). India Standard Time is UTC+5:30 all year, London is UTC+0 in winter and UTC+1 during British Summer Time, and New York is UTC−5 in winter and UTC−4 during daylight saving time. To convert, subtract the source offset to get UTC, then add the target offset.

Because daylight-saving rules change by date, always convert for the specific date of your meeting rather than assuming a fixed gap.

Worked example

A call at 9:00 AM in New York on 15 January (UTC−5) is 14:00 UTC, which is 19:30 IST and 14:00 in London. On 15 July, New York is on daylight time (UTC−4), so 9:00 AM there is 13:00 UTC, which is 18:30 IST and 14:00 in London (UTC+1).

Common pitfalls

Daylight saving starts and ends on different dates in different countries, so the gap between two cities can change by an hour for a few weeks each year. Some zones use 30- or 45-minute offsets, such as India (+5:30) and Nepal (+5:45). When scheduling across zones, always state the time zone explicitly in invitations.