Timezone Converter
Convert times between timezones effortlessly with our Timezone Converter. Select source and target timezones from the comprehensive IANA timezone database, enter any date and time, and get accurate conversions instantly. Perfect for scheduling international meetings, coordinating with remote teams, planning travel, or converting event times for global audiences. The tool automatically handles daylight saving time transitions, ensuring accuracy year-round. Your local timezone is pre-selected for convenience, making quick conversions even faster. Copy the converted time with one click for easy sharing in emails or calendars. All conversions use the browser's built-in Intl APIs for maximum accuracy and reliability. Ideal for remote workers, international businesses, travelers, or anyone coordinating across time zones.
What Is a Timezone Converter?
A timezone converter translates a specific date and time from one time zone to another. With remote teams spanning continents, global clients, and international travel, converting time zones accurately is a daily necessity. Mistakes — scheduling a meeting at 9 AM EST while your UK colleague is already at midnight — waste everyone's time and signal poor attention to detail.
Timezone conversion is complicated by Daylight Saving Time (DST), which shifts clocks by one hour in spring and back in fall — on different dates in the US, Europe, and other regions. Some countries like India (UTC+5:30) and Iran (UTC+3:30) use non-integer hour offsets. This tool handles all IANA time zones with accurate DST rules so you don't have to track these manually.
How to Use This Timezone Converter
- Enter the date and time you want to convert in the source field.
- Select the source time zone from the dropdown (e.g., America/New_York for EST/EDT).
- Select the target time zone to convert to.
- The converter shows the equivalent time, accounting for any DST offset differences.
- Add multiple target zones to compare across teams in different regions simultaneously.
Worked Example: Global Team Meeting at 2 PM PST
US West Coast call scheduled for 2:00 PM PST (UTC−8) in winter (non-DST):
2:00 PM PST → equivalent times globally:
Note: In summer (DST), PST becomes PDT (UTC−7), shifting all conversions by +1 hour. London switches to BST (UTC+1), making it UTC+9 from PST instead of UTC+8 — this can cause a 2-hour effective shift if only one side observes DST at that moment.
World Time Zone Reference
| Abbreviation | Full Name | UTC Offset (Standard) | Major Cities |
|---|---|---|---|
| PST / PDT | Pacific Standard / Daylight | UTC−8 / UTC−7 | Los Angeles, Seattle, Vancouver |
| MST / MDT | Mountain Standard / Daylight | UTC−7 / UTC−6 | Denver, Phoenix, Calgary |
| CST / CDT | Central Standard / Daylight | UTC−6 / UTC−5 | Chicago, Dallas, Mexico City |
| EST / EDT | Eastern Standard / Daylight | UTC−5 / UTC−4 | New York, Miami, Toronto |
| GMT / BST | Greenwich / British Summer | UTC+0 / UTC+1 | London, Dublin, Reykjavik |
| CET / CEST | Central European Time | UTC+1 / UTC+2 | Paris, Berlin, Rome, Madrid |
| EET / EEST | Eastern European Time | UTC+2 / UTC+3 | Athens, Cairo, Helsinki |
| IST | India Standard Time | UTC+5:30 | Mumbai, New Delhi, Bangalore |
| CST | China Standard Time | UTC+8 | Beijing, Shanghai, Hong Kong |
| JST | Japan Standard Time | UTC+9 | Tokyo, Osaka, Seoul |
| AEST / AEDT | Australian Eastern Time | UTC+10 / UTC+11 | Sydney, Melbourne, Brisbane |
Key Concepts: UTC, DST, and IANA Time Zones
UTC (Coordinated Universal Time) is the global time standard. All time zones are expressed as UTC±offset. Unlike GMT (which was historically based on the Royal Observatory in Greenwich), UTC is an atomic standard that does not change with DST. UTC is the reference for aviation, internet protocols, financial markets, and server timestamps.
Daylight Saving Time (DST) shifts clocks forward by one hour in spring (“spring forward”) and back in fall (“fall back”). The US moves clocks on the second Sunday of March and first Sunday of November. Most of Europe changes on the last Sunday of March and October. Countries like Arizona (US), Japan, China, and most of Africa do not observe DST, creating variable offsets that change throughout the year.
IANA Time Zone Database (also called tz database or Olson database) is the authoritative source for all timezone rules worldwide. It uses names like “America/New_York” or “Europe/London” rather than abbreviations like EST or BST, because abbreviations are ambiguous (IST means India Standard Time, Ireland Standard Time, and Israeli Standard Time). Always use IANA names in software for correctness.
Tips for Scheduling Across Time Zones
Anchor to UTC for scheduling. When coordinating across many time zones, share times in UTC to avoid confusion. “Meeting at 14:00 UTC” is unambiguous anywhere in the world. Calendar apps like Google Calendar and Outlook handle UTC conversions automatically if each user sets their local time zone correctly.
Watch for DST transition weeks. During the 2–3 weeks when the US has shifted clocks but Europe has not (or vice versa), the time difference changes by 1–2 hours. A recurring Monday 9 AM meeting can suddenly show up at 10 AM in the other location. Always re-confirm meeting times during March–April and October–November.
Respect working hours. A fair team meeting window for US West Coast + Europe is extremely narrow: 9 AM PST = 6 PM CET, the outer edge of European working hours. Including Asia-Pacific makes it nearly impossible to find a single slot covering all regions — rotate the meeting time to share the burden equitably across time zones.
Frequently Asked Questions
What is UTC and how does it differ from GMT?
UTC (Coordinated Universal Time) is the current international time standard, kept by atomic clocks and not adjusted for DST. GMT (Greenwich Mean Time) was the historical standard and still refers to the time at the Prime Meridian in Greenwich, UK. In practice, UTC and GMT are the same offset (UTC±0), but UTC is the official reference used in aviation, computing, and finance.
Why do some countries not observe Daylight Saving Time?
Countries near the equator have consistent day length year-round, making DST unnecessary. Japan, China, India, and most of Africa do not observe DST. The US state of Arizona also doesn't (except the Navajo Nation). As of 2024, the EU has proposed abolishing DST across Europe. The result is that some UTC offsets change seasonally between regions.
What does UTC+5:30 mean for India?
IST (India Standard Time) is UTC+5:30 — 5 hours and 30 minutes ahead of UTC. This non-integer offset exists for geographic and historical reasons. India uses a single time zone for the entire country despite spanning a geographic range that could justify multiple zones. This means sunrise and sunset times vary significantly across the subcontinent.
How do I convert time zones without a calculator?
Memorize key UTC offsets: PST=UTC−8, EST=UTC−5, GMT=UTC±0, CET=UTC+1, IST=UTC+5:30, JST=UTC+9. To convert: add your local UTC offset to get UTC, then add the target's UTC offset. Example: 3 PM EST (UTC−5) → 3+5=8 PM UTC → 8+9=5 AM+1 JST (Tokyo). Add 24 for next day if result exceeds 23.
What is the International Date Line?
The International Date Line (IDL) runs roughly along the 180° meridian in the Pacific Ocean (with deviations to keep island groups in the same date). Crossing it westbound moves your calendar forward one day; eastbound moves it back one day. This is why flights from Los Angeles to Tokyo (crossing the IDL westbound) arrive the next calendar day, while the return may arrive the same calendar day you left.
What time zones does the US use?
The contiguous US has four main time zones: Pacific (UTC−8/−7 DST), Mountain (UTC−7/−6), Central (UTC−6/−5), and Eastern (UTC−5/−4). Alaska uses AKST (UTC−9) and Hawaii uses HST (UTC−10, no DST). US territories like Puerto Rico are on AST (UTC−4, no DST). Arizona (except Navajo Nation) stays on MST year-round without DST.
How does time zone scheduling work in calendar apps?
Calendar apps like Google Calendar, Outlook, and Apple Calendar store events in UTC internally. When you create an event, it records the UTC timestamp. It then displays the event in your local time zone. If you share an event with someone in another time zone, they see the correct local equivalent. If a user changes their device time zone, events update automatically.
What is epoch time?
Epoch time (Unix timestamp) is the number of seconds elapsed since January 1, 1970, 00:00:00 UTC. It is the universal time representation in software, databases, and APIs. Unlike local times, Unix timestamps are unambiguous — they are time-zone-independent. Converting epoch time to human-readable form requires specifying a target time zone for the display offset.