Convert time between cities
Pick two cities and optionally a time and date. You get the current time in both, the exact difference including daylight-saving changes, and a 24-hour table with overlapping office hours highlighted, so scheduling a call takes seconds.
How to use the Time Zone Converter
- Choose the city you are in and the city you want to compare.
- Leave time blank for "now", or enter a time and date.
- Click Convert; read the difference and the working-hours overlap table.
Why time differences change during the year
Many countries move their clocks forward in spring and back in autumn (daylight saving time), but on different dates: the USA and Canada change on the second Sunday of March and first Sunday of November, the UK and EU on the last Sundays of March and October, Australia and New Zealand in the opposite direction in October and April, and most of Asia, Africa and the Middle East not at all. So London and New York are usually 5 hours apart, but 4 hours for two weeks in March and one week in November. This tool uses your browser's built-in time-zone database, which tracks those rules for every zone, and calculates the difference for the exact date you enter.
Reading the table
The hour-by-hour table maps each hour of the day in the first city to the corresponding hour in the second, with "next day" or "previous day" marked where the date differs. Rows highlighted in green fall within 09:00–18:00 in both cities, which is the window for a call that is not painful for either side. If there is no green row, one side will have to take an early or late call; the rows nearest the boundary are the fairest.
UTC and offsets
Each city shows its current offset from Coordinated Universal Time, for example UTC+05:00 for Karachi or UTC−08:00 for Los Angeles in winter. Offsets are what airline schedules and servers use; abbreviations like EST, BST or PKT are shown too but are ambiguous (IST is India, Ireland and Israel), so prefer the offset in written arrangements.
Frequently asked questions
Does it account for daylight saving time?
Yes. It uses the IANA time-zone rules built into your browser, so the difference is correct for the specific date.
Can I add my own city?
Choose the nearest city in the same time zone; every city in a zone shares the same time. More cities are being added.
What time is "now" based on?
Your device clock, converted through the selected zones.
Privacy
This tool runs entirely inside your browser using WebAssembly and the Canvas/File APIs. Your files are never uploaded to ToolFlint or any third party; you can verify this in your browser's network tab or by switching to airplane mode after the page loads. Read how we process files.
Last updated 2026-09-23.