Time Zone Converter

How to use the Time Zone Converter

1. 1

   Check the source city. It starts as your own time zone; search to change it to any city or IANA zone.

2. 2

   Set the date and time you want to convert, or press Now for the current time.

3. 3

   Add the cities you need with the search box and remove the ones you don't with the X button.

4. 4

   Read each city's local time, date and UTC offset. A "+1 day" or "−1 day" tag means the date is different from the source.

5. 5

   Scroll to the meeting planner to see which hours fall inside 9:00 to 17:00 everywhere.

UTC offsets: the number behind every time zone

Every civil time zone is defined by its offset from Coordinated Universal Time (UTC), the reference clock kept by atomic clocks and used by aviation, the internet and science. London in winter is UTC+00:00, New York in winter is UTC−05:00, and Tokyo is UTC+09:00 all year. To convert between two places, you convert to UTC and then to the other offset. At 15:00 in Tokyo it is 06:00 UTC, which is 01:00 in New York in January.

Offsets are not always whole hours. Several places use half-hour or even 45-minute steps, which is a frequent source of scheduling mistakes:

The converter uses the IANA time zone database built into your browser, the same data phones and calendar apps use. A zone such as America/New_York records not only the current offset but the full history of rule changes, which is why it is more reliable than typing "EST" or "GMT+5".

How daylight saving time shifts the gaps between cities

Daylight saving time (DST), called summer time in the UK and much of Europe, moves clocks forward by an hour in spring and back in autumn. The difficulty for international planning is that countries change on different dates, and the Northern and Southern Hemispheres move in opposite directions.

• The United States and most of Canada switch on the second Sunday in March and the first Sunday in November.
• The European Union and the UK switch on the last Sunday in March and the last Sunday in October.
• Australia's southeastern states and New Zealand switch in the opposite season, starting in late September or early October and ending in early April.
• Most of Asia, Africa and South America do not use DST at all, including India, China, Japan, Singapore, the UAE, Nigeria, Kenya, Brazil and Argentina. Most of Mexico stopped in 2022. In the US, Hawaii and most of Arizona stay on standard time all year, and in Australia, Queensland does too.

Because of these mismatches, the gap between New York and London is usually five hours but drops to four for a few weeks each March and for about a week around the end of October. Sydney can be anywhere from 14 to 16 hours ahead of New York depending on the month. Entering the actual date avoids missed meetings in those weeks.

Times that don't exist, and times that happen twice

When clocks spring forward, an hour of local time is skipped. In New York on 8 March 2026, clocks jump from 01:59 straight to 03:00, so 02:30 never happens. If you enter a skipped time, the converter tells you and treats it as the moment it would have been, which reads as 03:30 local time.

When clocks fall back, an hour repeats. On 1 November 2026, 01:30 occurs twice in New York, first in daylight time (UTC−04:00) and then an hour later in standard time (UTC−05:00). The converter flags this and lets you pick the first or second occurrence. Avoid booking anything important in that window.

Tips for scheduling international meetings

The meeting planner lays out one full day in the source city and shows the matching local hour in every other city. Green cells are between 9:00 and 17:00, amber cells are early morning or evening, and grey cells are night. Hours that are green for every city are outlined.

• Europe and India overlap comfortably in the European morning: 10:00 in Berlin is 14:30 in Mumbai in winter and 13:30 in summer.
• The US East Coast and Western Europe share roughly the European afternoon and the American morning. 15:00 in London is 10:00 in New York for most of the year.
• The US West Coast and East Asia have almost no shared office hours. Teams in San Francisco and Singapore or Tokyo usually rotate between late-afternoon calls on one side and early-morning calls on the other.
• Watch the working week. In Saudi Arabia, Qatar and Kuwait the weekend is Friday and Saturday, so a Friday slot that works for London may land on a day off.
• When you send an invite, write the time with the city or the UTC offset, such as "14:00 UTC (15:00 Berlin, 19:30 Mumbai)".

Time zone abbreviations can be misleading

Short names such as CST, IST or BST are not unique. CST can mean Central Standard Time in North America or China Standard Time. IST is used for India, Ireland and Israel. Many people also say EST in summer when New York is actually on EDT. The converter shows abbreviations where your browser provides them, but always alongside the numeric UTC offset, which is the unambiguous part.