Convert time between cities worldwide. See current local time and time differences instantly.
The Earth is divided into 24 time zones, each offset from UTC (Coordinated Universal Time). Moving east adds hours, moving west subtracts.
UTC is the global reference. New York is UTC-5 (or UTC-4 during daylight saving), London is UTC+0 (or UTC+1 BST), Tokyo is UTC+9. Some zones use half-hour offsets: India (UTC+5:30), Nepal (UTC+5:45).
Daylight saving time (DST) shifts clocks forward 1 hour in spring and back in fall in many countries. This changes the UTC offset seasonally.
Not all countries observe DST. The US, Canada, and most of Europe do. Most of Asia, Africa, and South America do not. This converter uses your browser's timezone data which accounts for DST automatically based on the current date.
Here are the most commonly referenced time zones for international business, travel, and remote work.
| Zone | UTC Offset | Major Cities |
|---|---|---|
| PST/PDT | UTC−8/−7 | Los Angeles, Seattle, Vancouver |
| MST/MDT | UTC−7/−6 | Denver, Phoenix (no DST) |
| CST/CDT | UTC−6/−5 | Chicago, Dallas, Mexico City |
| EST/EDT | UTC−5/−4 | New York, Toronto, Miami |
| GMT/BST | UTC+0/+1 | London, Dublin, Lisbon |
| CET/CEST | UTC+1/+2 | Paris, Berlin, Rome, Madrid |
| EET/EEST | UTC+2/+3 | Bucharest, Athens, Helsinki |
| IST | UTC+5:30 | Mumbai, Delhi, Bangalore |
| CST (China) | UTC+8 | Beijing, Shanghai, Singapore |
| JST | UTC+9 | Tokyo, Seoul |
| AEST/AEDT | UTC+10/+11 | Sydney, Melbourne |
India (UTC+5:30), Iran (UTC+3:30), Nepal (UTC+5:45), and several other regions use non-standard offsets because the standard hourly zones didn't align well with their geography or solar noon.
India spans nearly 30° of longitude (enough for 2 time zones), but chose a single UTC+5:30 offset as a political compromise — placing solar noon roughly in the center of the country. This means sunrise in the far east (Arunachal Pradesh) is nearly 2 hours earlier than in the far west (Gujarat). Nepal chose UTC+5:45 partly to differentiate from India and partly because it better aligns with Kathmandu's solar noon. The Chatham Islands (New Zealand territory) use UTC+12:45, making them one of the earliest places on Earth to see a new day. Australia's Northern Territory uses UTC+9:30 while South Australia uses UTC+9:30 with DST (shifting to +10:30 in summer), creating the unusual situation where two regions share a time zone in winter but differ by one hour in summer.
The International Date Line (IDL) runs roughly along the 180° meridian in the Pacific Ocean. Crossing it westward skips forward one day; crossing eastward goes back one day.
The IDL isn't a straight line — it zigzags around island nations. Samoa switched from the east side to the west side of the IDL in 2011, skipping December 30 entirely, to align business hours with Australia and New Zealand (its major trading partners) rather than the US. Kiribati did something even more dramatic in 1995: it moved the IDL eastward so that all of its islands (spread across 5,000 km of Pacific Ocean) would share the same day, making the Line Islands the first inhabited place to enter each new year. This is why Kiritimati (Christmas Island) in Kiribati is UTC+14 — the furthest ahead of any time zone in the world, 26 hours ahead of Baker Island (UTC-12), despite being only ~2,000 km apart.
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Note: Time conversions use your browser's built-in timezone data (IANA Time Zone Database) which accounts for daylight saving time. For historical date conversions, DST rules may differ from current rules.
With remote work and global teams becoming the norm, understanding time zones is more important than ever. The world is divided into 24 major time zones, each roughly 15 degrees of longitude wide. However, political boundaries and daylight saving time (DST) create complexities that make a converter essential for scheduling across borders.
All time zones are relative to UTC (Coordinated Universal Time), based in Greenwich, London. Major cities: New York = UTC-5 (EST) / UTC-4 (EDT). London = UTC+0 (GMT) / UTC+1 (BST). Bucharest = UTC+2 (EET) / UTC+3 (EEST). Dubai = UTC+4. Mumbai = UTC+5:30. Tokyo = UTC+9. Sydney = UTC+11 (AEDT). When it is noon in New York, it is 5 PM in London, 7 PM in Bucharest, 9 PM in Dubai, and 3 AM (next day) in Sydney.
About 70 countries observe DST, but they do not all change on the same dates. The US "springs forward" in March, Europe in late March, and Australia in October (Southern Hemisphere has opposite seasons). Some regions within countries do not observe DST at all (Arizona in the US, Queensland in Australia). This means the time difference between two cities can change 2-4 times per year. India, China, and Japan never observe DST. Always verify current offsets when scheduling important international meetings.