You pick two to six places, enter a date and a time in any of them, and the tool shows what the clock says everywhere else at that same moment. Under the results a 24-hour grid lines the places up hour by hour, shading night and normal working hours, so you can see at a glance when a call suits everyone. It handles daylight saving time from the time zone data your browser already has, and it shows its working when a time is odd: a time that does not exist, or one that happens twice. The whole state lives in the page address, so a link to the page is a link to your comparison. Nothing is sent to a server.
Reading the grid
The grid covers the 24 hours that start at midnight on your chosen date in the entered-in place. Each row shows what the clock reads in one place during those hours. Night is 22:00 to 06:00 on that place's own clock, shown dark with a moon, and work hours are 09:00 to 18:00, shown tinted. Colour is not the only signal: night cells carry a moon and all cells are named for screen readers. A thick line and a short weekday name mark the column where a place's calendar day changes. Places with half-hour or 45-minute offsets, such as India (GMT+5:30) and Nepal (GMT+5:45), show their minutes in every cell.
Daylight saving, done properly
A time zone is more than a fixed number of hours: it is a set of rules, and the rules differ. In 2026 the United States moved its clocks on 8 March and 1 November, Europe on 29 March and 25 October, and Sydney on 4 October and 5 April. Because the dates differ, the gap between New York and London is 5 hours for most of the year but 4 hours for three weeks in March and one week in October: 09:00 in New York on Tuesday 10 March is 13:00 in London. Vietnam has no daylight saving and is always GMT+7. Lord Howe Island changes by only 30 minutes. This tool never keeps a table of offsets. It asks the browser for the real offset at each moment, so the answer is right for any date the data covers, in both hemispheres.
When a time does not exist, or happens twice
On the day clocks go forward, an hour is skipped: in New York 02:30 on 8 March 2026 never happens. The tool says so and moves to 03:30, which is what a clock that kept running would show. On the day clocks go back, an hour happens twice: 01:30 on 1 November 2026 in New York is 05:30 UTC the first time and 06:30 UTC the second. The tool shows the first one and offers a switch for the second. In the most extreme case, Samoa skipped the whole of 30 December 2011 when it crossed the date line.
A worked example and good to know
Take 09:00 on Thursday 15 October 2026 in Ho Chi Minh City. That is 02:00 UTC, 03:00 in London (GMT+1 with daylight saving), 07:30 in India, 13:00 in Sydney and 22:00 on Wednesday 14 October in New York (GMT-4). Everything you enter stays in the page address after the # sign, which browsers never send to a server, so the link is safe to share. Time zone rules change several times a year, and a rule that is not yet published cannot be known: dates far in the future use the current rules. The labels use the usual GMT+7 form; be careful with the zone names Etc/GMT+7 and similar, where the sign is the opposite. To convert a single timestamp or date instead, use the timestamp converter, and to see when a scheduled job will run in a given zone, the cron expression explainer.
