Timezone Converter
Convert dates and times between world timezones using the IANA timezone database for accurate DST-aware conversions.
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Date & Time
Target Timezone
Result
About Timezone Converter
This timezone converter converts dates and times between world timezones using the IANA timezone database for accurate, DST-aware conversions. It handles historical timezone rules and automatic daylight saving time adjustments.
It is useful for scheduling international meetings, coordinating remote teams across continents, planning travel itineraries, converting webinar/podcast recording times, setting up global conference calls, flight booking across timezones, and any scenario requiring accurate cross-region time coordination.
World Timezone Reference
| Region | Timezone | UTC Offset | DST Observed |
|---|---|---|---|
| Eastern US | America/New_York | UTC-5 / UTC-4 | Yes (Mar-Nov) |
| Central US | America/Chicago | UTC-6 / UTC-5 | Yes (Mar-Nov) |
| Mountain US | America/Denver | UTC-7 / UTC-6 | Yes (Mar-Nov) |
| Pacific US | America/Los_Angeles | UTC-8 / UTC-7 | Yes (Mar-Nov) |
| United Kingdom | Europe/London | UTC+0 / UTC+1 | Yes (Mar-Oct) |
| Central Europe | Europe/Paris | UTC+1 / UTC+2 | Yes (Mar-Oct) |
| Japan | Asia/Tokyo | UTC+9 | No |
| China | Asia/Shanghai | UTC+8 | No |
| India | Asia/Kolkata | UTC+5:30 | No |
| Australia (Sydney) | Australia/Sydney | UTC+10 / UTC+11 | Yes (Oct-Apr) |
UTC Offset Reference by US City
| City | Timezone | Standard | Daylight |
|---|---|---|---|
| New York | America/New_York | EST (UTC-5) | EDT (UTC-4) |
| Chicago | America/Chicago | CST (UTC-6) | CDT (UTC-5) |
| Denver | America/Denver | MST (UTC-7) | MDT (UTC-6) |
| Los Angeles | America/Los_Angeles | PST (UTC-8) | PDT (UTC-7) |
| Phoenix | America/Phoenix | MST (UTC-7) | No DST |
| Honolulu | Pacific/Honolulu | HST (UTC-10) | No DST |
Daylight Saving Time Schedule
DST transition dates vary by region:
| Region | DST Starts | DST Ends | Offset Change |
|---|---|---|---|
| United States | 2nd Sunday in March | 1st Sunday in November | +1 hour |
| European Union | Last Sunday in March | Last Sunday in October | +1 hour |
| United Kingdom | Last Sunday in March | Last Sunday in October | +1 hour |
| Australia | 1st Sunday in October | 1st Sunday in April | +1 hour |
Note: Southern Hemisphere DST is reversed (summer = Oct-Apr). Some regions don't observe DST at all.
Timezone Conversion Examples
Example 1: US East to West Coast Input: 2024-03-15 09:00 (New York) Output: 2024-03-15 06:00 (Los Angeles) Difference: -3 hours (EDT to PDT) Example 2: London to Tokyo Input: 2024-06-01 14:00 (London) Output: 2024-06-01 22:00 (Tokyo) Difference: +8 hours (BST to JST) Example 3: New York to Sydney Input: 2024-01-15 10:00 (New York) Output: 2024-01-16 02:00+1 (Sydney) Difference: +16 hours (EST to AEDT, next day) Example 4: During DST Transition Input: 2024-03-10 01:30 (New York) Output: Skips to 03:00 EDT (DST starts) Note: 2:00 AM jumps to 3:00 AM Example 5: During Fall Back Input: 2024-11-03 01:30 (New York) Output: Occurs twice (EDT then EST) Note: 2:00 AM repeats as 1:00 AM
Common Use Cases
- Remote Team Meetings: Find overlapping business hours for distributed teams across US, Europe, and Asia
- Webinar Scheduling: Convert presentation times to multiple timezones for global audience registration pages
- Travel Planning: Calculate arrival times and jet lag duration when booking international flights
- Software Releases: Coordinate deployment times across engineering teams in different regions
- Customer Support: Display support availability in customer's local timezone
- Broadcast Scheduling: Announce live stream times in viewer-friendly local times
IANA Timezone Format
The IANA timezone database uses Region/City format:
Format: Continent/City or Ocean/Region Americas: America/New_York - Eastern Time America/Chicago - Central Time America/Denver - Mountain Time America/Los_Angeles - Pacific Time America/Anchorage - Alaska Time Pacific/Honolulu - Hawaii Time Europe: Europe/London - GMT/BST Europe/Paris - CET/CEST Europe/Berlin - CET/CEST Europe/Moscow - MSK (no DST) Asia: Asia/Dubai - GST (UTC+4) Asia/Kolkata - IST (UTC+5:30) Asia/Bangkok - ICT (UTC+7) Asia/Shanghai - CST (UTC+8) Asia/Tokyo - JST (UTC+9) Asia/Seoul - KST (UTC+9) Pacific: Australia/Sydney - AEST/AEDT Pacific/Auckland - NZST/NZDT
Timezone Abbreviation Reference
| Abbreviation | Full Name | UTC Offset |
|---|---|---|
| UTC | Coordinated Universal Time | UTC+0 |
| GMT | Greenwich Mean Time | UTC+0 |
| EST | Eastern Standard Time | UTC-5 |
| EDT | Eastern Daylight Time | UTC-4 |
| CST | Central Standard Time (US) / China Standard Time | UTC-6 / UTC+8 |
| MST | Mountain Standard Time | UTC-7 |
| PST | Pacific Standard Time | UTC-8 |
| JST | Japan Standard Time | UTC+9 |
| IST | Indian Standard Time / Irish Standard Time | UTC+5:30 / UTC+1 |
Note: Some abbreviations are ambiguous (CST, IST). Always use IANA format for clarity.
Frequently Asked Questions
- What is the IANA timezone database?
- The IANA Time Zone Database (also called tz database or zoneinfo) is a collaborative collection of timezone information used by most operating systems and programming languages. It uses Region/City format (America/New_York, Europe/London, Asia/Tokyo) and includes historical timezone rules plus DST transition dates.
- What is the difference between UTC and GMT?
- UTC (Coordinated Universal Time) is a time standard based on atomic clocks. GMT (Greenwich Mean Time) is a timezone based on Earth's rotation. For most practical purposes they're identical (UTC+0 = GMT), but UTC is used for technical/scientific applications while GMT is a civil timezone. UTC doesn't observe DST; some GMT regions do.
- How does Daylight Saving Time affect conversions?
- DST shifts clocks forward (usually +1 hour) during summer months. The converter automatically accounts for DST based on the date and timezone rules. For example, New York is UTC-5 (EST) in winter but UTC-4 (EDT) in summer. European timezones also shift; most US states observe DST but Arizona and Hawaii don't.
- Why use Region/City format instead of EST/PST?
- Abbreviations like EST, PST, CST are ambiguous (Australia has CST too) and don't account for DST changes. IANA format (America/New_York, America/Los_Angeles) is unambiguous and automatically handles DST transitions. It also accounts for historical timezone rule changes that abbreviations can't represent.
- What are common US timezone abbreviations?
- US timezones: ET/EST/EDT (Eastern, UTC-5/-4), CT/CST/CDT (Central, UTC-6/-5), MT/MST/MDT (Mountain, UTC-7/-6), PT/PST/PDT (Pacific, UTC-8/-7), AKST/AKDT (Alaska, UTC-9/-8), HST (Hawaii, UTC-10, no DST). The 'S' = Standard (winter), 'D' = Daylight (summer).
- How do I schedule meetings across timezones?
- First, identify all participant timezones. Use a timezone converter to find overlapping business hours. Consider rotating meeting times if the schedule disadvantages one region. Use UTC for calendar invites to avoid confusion. Tools like World Time Buddy or calendar apps with multiple timezone display help visualize overlap windows.