Time Zone Converter
Convert times between different time zones around the world.
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About This Calculator
The Time Zone Converter instantly converts time between any two time zones worldwide, making it essential for scheduling international meetings, coordinating with remote teams, planning calls across countries, or understanding what time it is anywhere in the world. With over 24 major time zones and numerous regional variations, converting times accurately can be challenging—especially when factoring in Daylight Saving Time transitions that occur at different dates in different countries. Whether you're a business professional scheduling calls with colleagues in Tokyo, London, and New York, a traveler planning activities in a different time zone, or a remote worker coordinating with a globally distributed team, this converter handles the complexity automatically. Our tool accounts for DST changes in both the source and destination locations, shows you when dates change due to time differences, and helps you find optimal meeting times that work across multiple time zones. In our increasingly connected world where remote work spans continents and international collaboration is the norm, understanding time zones has become a critical everyday skill.
How to Use the Time Zone Converter
- 1Select your local time zone from the dropdown or use auto-detect based on your device settings.
- 2Enter the time you want to convert using 12-hour or 24-hour format.
- 3Choose the target time zone you want to convert to.
- 4View the converted time with clear date change indication if the day differs.
- 5Use the meeting planner to see multiple time zones at once for group scheduling.
- 6Toggle between standard time and daylight saving time if needed for future planning.
- 7Check the DST status indicator to see if either location is currently observing DST.
- 8Bookmark commonly used conversions for quick access in the future.
Understanding Time Zones
How Time Zones Work: The Earth is divided into 24 standard time zones, each roughly 15 degrees of longitude wide (360° ÷ 24 = 15°). Each zone differs by approximately one hour from adjacent zones.
The Prime Meridian and UTC:
- Time zones are measured from the Prime Meridian (0° longitude) passing through Greenwich, London
- UTC (Coordinated Universal Time) is the global time standard, essentially the same as GMT
- Time zones west of Greenwich are negative (UTC-5 for New York), east are positive (UTC+9 for Tokyo)
UTC Offset Ranges:
- Westernmost: UTC-12 (uninhabited areas, Line Islands)
- Easternmost: UTC+14 (Kiribati's Line Islands)
- This means the world spans 26 hours of time at any moment!
Major Time Zone Abbreviations:
| Abbreviation | Full Name | UTC Offset |
|---|---|---|
| EST/EDT | Eastern Standard/Daylight | -5/-4 |
| CST/CDT | Central Standard/Daylight | -6/-5 |
| MST/MDT | Mountain Standard/Daylight | -7/-6 |
| PST/PDT | Pacific Standard/Daylight | -8/-7 |
| GMT | Greenwich Mean Time | 0 |
| CET/CEST | Central European Time | +1/+2 |
| IST | India Standard Time | +5:30 |
| JST | Japan Standard Time | +9 |
| AEST/AEDT | Australian Eastern Time | +10/+11 |
Daylight Saving Time (DST)
When DST Changes Occur:
North America:
- Begins: 2nd Sunday of March (clocks forward 1 hour)
- Ends: 1st Sunday of November (clocks back 1 hour)
- Mnemonic: "Spring forward, Fall back"
European Union:
- Begins: Last Sunday of March
- Ends: Last Sunday of October
Australia (Southern Hemisphere - Reversed):
- Begins: 1st Sunday of October
- Ends: 1st Sunday of April
Regions That Do NOT Observe DST:
- Arizona (US, except Navajo Nation)
- Hawaii
- Most of Asia (Japan, China, India, etc.)
- Most of Africa
- Most of South America
- Iceland
- Parts of Australia (Queensland, Northern Territory, Western Australia)
DST Impact on Time Differences: During DST transitions, the time difference between locations can change:
- New York to London is usually 5 hours
- During the 2-3 week gap when US has switched but EU hasn't: 4 hours
- When EU has switched but US hasn't: 6 hours
Why DST Exists: Originally implemented to save energy by maximizing daylight during waking hours. Modern studies show minimal energy savings, and many regions are reconsidering DST.
Major World Time Zones Reference
Quick Reference: Time Zone Offsets from UTC
| City | Standard Offset | DST Offset | DST? |
|---|---|---|---|
| Los Angeles | UTC-8 (PST) | UTC-7 (PDT) | Yes |
| Denver | UTC-7 (MST) | UTC-6 (MDT) | Yes |
| Chicago | UTC-6 (CST) | UTC-5 (CDT) | Yes |
| New York | UTC-5 (EST) | UTC-4 (EDT) | Yes |
| London | UTC+0 (GMT) | UTC+1 (BST) | Yes |
| Paris/Berlin | UTC+1 (CET) | UTC+2 (CEST) | Yes |
| Cairo | UTC+2 (EET) | - | No |
| Moscow | UTC+3 (MSK) | - | No |
| Dubai | UTC+4 (GST) | - | No |
| Mumbai | UTC+5:30 (IST) | - | No |
| Singapore | UTC+8 (SGT) | - | No |
| Hong Kong | UTC+8 (HKT) | - | No |
| Tokyo | UTC+9 (JST) | - | No |
| Sydney | UTC+10 (AEST) | UTC+11 (AEDT) | Yes |
| Auckland | UTC+12 (NZST) | UTC+13 (NZDT) | Yes |
Non-Standard Offsets (30/45 minutes):
- India: UTC+5:30
- Iran: UTC+3:30
- Nepal: UTC+5:45
- Afghanistan: UTC+4:30
- Myanmar: UTC+6:30
- Central Australia: UTC+9:30
- Newfoundland, Canada: UTC-3:30
- Chatham Islands, NZ: UTC+12:45
International Meeting Scheduling
Finding Overlapping Business Hours:
For a meeting between New York, London, and Tokyo:
| NYC Time | London | Tokyo | Notes |
|---|---|---|---|
| 6:00 AM | 11:00 AM | 8:00 PM | Early for NYC |
| 7:00 AM | 12:00 PM | 9:00 PM | Early NYC, late Tokyo |
| 8:00 AM | 1:00 PM | 10:00 PM | Very late for Tokyo |
| 5:00 PM | 10:00 PM | 7:00 AM+1 | Late London, early Tokyo next day |
Best practices for global meetings:
The "Follow the Sun" approach:
- NYC: 8 AM (start of day)
- London: 1 PM (afternoon)
- Tokyo: 10 PM (end of day, but manageable)
Tips for Inclusive Scheduling:
- Rotate meeting times to share the inconvenience
- Record meetings for those who cannot attend
- Use async communication (Slack, email) when possible
- Establish "core hours" when everyone should be available
- Use scheduling tools that show multiple time zones
- Consider splitting into regional meetings with summaries
Time Zone Etiquette:
- Always specify the time zone when scheduling (e.g., "3 PM EST")
- Use 24-hour format to avoid AM/PM confusion
- Send calendar invites that automatically adjust for recipient's zone
- Provide a link to a world clock or converter
Time Zone Conversions from EST (New York)
Quick Conversion Chart from Eastern Time (EST/EDT):
| Destination | Hours Difference | Example (EST 9 AM) |
|---|---|---|
| Los Angeles (PST) | -3 hours | 6 AM |
| Chicago (CST) | -1 hour | 8 AM |
| London (GMT) | +5 hours | 2 PM |
| Paris (CET) | +6 hours | 3 PM |
| Berlin (CET) | +6 hours | 3 PM |
| Cairo (EET) | +7 hours | 4 PM |
| Dubai (GST) | +9 hours | 6 PM |
| Mumbai (IST) | +10.5 hours | 7:30 PM |
| Singapore (SGT) | +13 hours | 10 PM |
| Hong Kong (HKT) | +13 hours | 10 PM |
| Tokyo (JST) | +14 hours | 11 PM |
| Sydney (AEST) | +15 hours | 12 AM+1 |
| Auckland (NZST) | +17 hours | 2 AM+1 |
Mental Math Tricks:
- London is 5 hours ahead of New York (standard time)
- Tokyo is 14 hours ahead of New York
- When it's 9 AM Monday in NYC, it's 11 PM Monday in Tokyo
- Sydney is "tomorrow" compared to New York most of the day
Date Line Considerations:
- Traveling west across the International Date Line: add a day
- Traveling east across the International Date Line: subtract a day
Remote Work and Global Teams
Common Remote Work Time Zone Challenges:
US Company with Global Team:
| Team Location | Overlap with US EST (9-5) |
|---|---|
| UK/Europe | 3-4 hours (9 AM - 12 PM EST) |
| India | 1 hour or evening call |
| Australia | Near-zero or very early/late |
| Latin America | 0-3 hours behind, good overlap |
Strategies for Global Teams:
Async-First Communication:
- Document decisions in writing
- Use video recordings for announcements
- Slack/Teams messages with clear deadlines
- Avoid expecting immediate responses
Core Hours Model:
- Identify 2-4 hours where all zones can overlap
- Reserve these for essential live meetings
- All other work happens asynchronously
Split Shift Approach:
- Some team members work offset hours
- 10 AM - 6 PM shifts become 6 AM - 2 PM or 2 PM - 10 PM
Regional Hub Model:
- Americas hub, EMEA hub, APAC hub
- Meetings within hubs, async between hubs
- Periodic all-hands at rotating times
Tools for Remote Teams:
- World Time Buddy, Every Time Zone
- Slack timezone display
- Google Calendar's "Find a time" feature
- Calendly with time zone auto-detection
The International Date Line
What Is the International Date Line?
The International Date Line (IDL) is an imaginary line running roughly along the 180° longitude in the Pacific Ocean. When you cross it:
- Westward (toward Asia): Add a day (Monday becomes Tuesday)
- Eastward (toward Americas): Subtract a day (Tuesday becomes Monday)
Why the IDL Exists: Without the date line, traveling around the world would accumulate or lose days. The IDL provides a fixed point where the calendar adjusts.
IDL Deviations: The line zigzags to keep certain island groups in the same day:
- Russia's Far East is on the same day as mainland Russia
- Kiribati crossed the line in 1995 to be on the same day as Australia
- Samoa skipped a day in 2011 to align with Australia/NZ trading partners
Interesting Effects:
- You can celebrate New Year twice by flying across the IDL
- Some neighboring islands are 25 hours apart despite being close
- Kiribati (UTC+14) is the first place to see each new day
- American Samoa (UTC-11) and Samoa (UTC+13) are only 70 miles apart but 24 hours different
Aviation and the Date Line:
- Flights from US to Asia often "arrive before they left" on paper
- Example: Leave LAX at 10 AM Monday, arrive Tokyo at 3 PM Tuesday (11-hour flight)
History of Time Zones
Before Standard Time Zones:
Before the late 1800s, each city set its own local time based on the sun's position. This caused chaos for:
- Railroad schedules (each station had different time)
- Business transactions
- Communication between cities
Railroad Time (1840s-1880s): Railroads created their own time zones, but each company used different standards. The US had over 300 local times!
Standard Time Zone Adoption:
| Year | Country | Notes |
|---|---|---|
| 1847 | Great Britain | First to standardize (Railway Time) |
| 1883 | United States | Railroads adopt 4 zones |
| 1884 | International | Prime Meridian Conference establishes GMT |
| 1918 | United States | Standard Time Act makes zones legal |
| 1972 | UTC | Coordinated Universal Time replaces GMT |
Sir Sandford Fleming: A Canadian railway engineer who proposed worldwide standard time zones in 1876. His system divided the world into 24 zones, each 15° of longitude wide.
Prime Meridian Conference (1884):
- 25 nations met in Washington, DC
- Established Greenwich as Prime Meridian (0° longitude)
- Created the framework for global time zones
- France abstained, using Paris Mean Time until 1911
Time Zones for Travelers
Managing Jet Lag:
Jet lag occurs when your body's internal clock doesn't match the local time. It's worse traveling east (harder to advance your clock) than west.
Jet Lag Recovery Times:
| Direction | Time Zones Crossed | Typical Recovery |
|---|---|---|
| East | 3-4 zones | 2-3 days |
| East | 5-6 zones | 4-6 days |
| East | 9-12 zones | 7-10 days |
| West | 3-4 zones | 1-2 days |
| West | 5-6 zones | 2-4 days |
| West | 9-12 zones | 4-7 days |
Tips for Minimizing Jet Lag:
- Start adjusting sleep schedule 2-3 days before travel
- Drink plenty of water during flight
- Get sunlight exposure at your destination
- Avoid heavy meals and alcohol
- Use melatonin for eastward travel (helps advance clock)
- Exercise during daylight hours at destination
Flight Time vs. Calendar Time:
| Route | Flight Time | Arrive vs. Depart |
|---|---|---|
| NYC → London | 7 hours | +5-6 hours calendar |
| NYC → Tokyo | 14 hours | +2 days calendar |
| LA → Sydney | 15 hours | +2 days calendar |
| NYC → LA | 6 hours | Same day, 3 hours later |
| London → Dubai | 7 hours | +4-5 hours calendar |
Pro tip for travelers: Set your watch to the destination time zone when you board the plane. Start eating and sleeping on the new schedule immediately.
Pro Tips
- 💡Always specify the time zone when scheduling international calls (e.g., "3 PM EST" not just "3 PM").
- 💡Double-check conversions during DST transition weeks in March/April and October/November.
- 💡Use UTC for scheduling to avoid ambiguity—it's the universal standard that never changes.
- 💡Remember: crossing the International Date Line changes the date, not just the time.
- 💡Set calendar events with time zones enabled so they auto-adjust for all participants.
- 💡When booking international flights, note departure/arrival are in local times of each city.
- 💡For global teams, rotate meeting times fairly—don't always burden the same time zone.
- 💡Use the 24-hour format (14:00 vs 2:00 PM) to avoid AM/PM confusion internationally.
- 💡Add world clocks to your phone home screen for time zones you frequently work with.
- 💡Japan, China, and India never observe DST—their offsets stay constant year-round.
- 💡London to New York is -5 hours (standard) but only -4 hours during the DST transition gap.
- 💡Australian DST is October-April (summer there), opposite of Northern Hemisphere.
Frequently Asked Questions
GMT (Greenwich Mean Time) and UTC (Coordinated Universal Time) are essentially the same time and are often used interchangeably. GMT is the historical term based on mean solar time at the Royal Observatory in Greenwich, London. UTC is the modern technical standard used by computers, aviation, and international communication. Neither GMT nor UTC observes Daylight Saving Time. The main difference is that UTC is more precisely defined using atomic clocks.
