Timezone Converter
Current Time Around the World
Convert Time Between Zones
Timezone Offset Reference
| Timezone | UTC Offset | Major Cities |
|---|---|---|
| HST | UTC-10:00 | Honolulu, Hawaii |
| AKST/AKDT | UTC-9/-8 | Anchorage, Alaska |
| PST/PDT | UTC-8/-7 | Los Angeles, Vancouver, Seattle |
| MST/MDT | UTC-7/-6 | Denver, Phoenix, Calgary |
| CST/CDT | UTC-6/-5 | Chicago, Houston, Mexico City |
| EST/EDT | UTC-5/-4 | New York, Toronto, Miami |
| BRT | UTC-3:00 | São Paulo, Rio de Janeiro |
| GMT/BST | UTC+0/+1 | London, Dublin, Lisbon |
| CET/CEST | UTC+1/+2 | Paris, Berlin, Rome, Madrid |
| EET/EEST | UTC+2/+3 | Athens, Cairo, Helsinki |
| MSK | UTC+3:00 | Moscow, Istanbul |
| GST/AST | UTC+4:00 | Dubai, Abu Dhabi, Muscat |
| AFT | UTC+4:30 | Kabul, Afghanistan |
| PKT | UTC+5:00 | Karachi, Lahore, Islamabad |
| IST (India) | UTC+5:30 | Mumbai, Delhi, Bangalore |
| NPT | UTC+5:45 | Kathmandu, Nepal |
| BST (Bangladesh) | UTC+6:00 | Dhaka, Bangladesh |
| ICT | UTC+7:00 | Bangkok, Jakarta, Ho Chi Minh |
| CST (China)/SGT | UTC+8:00 | Shanghai, Beijing, Singapore, Hong Kong |
| JST/KST | UTC+9:00 | Tokyo, Seoul, Osaka |
| AEST/AEDT | UTC+10/+11 | Sydney, Melbourne, Brisbane |
| NZST/NZDT | UTC+12/+13 | Auckland, Wellington |
How to Use This Tool
- View World Clocks: The top panel shows current time in major cities worldwide, updating live. Use this for quick timezone awareness when scheduling international meetings or deployments.
- Select Source Time: Choose the timezone you're converting from, then enter the date and time. If converting from your local time, your browser's timezone is pre-selected.
- Choose Target Timezones: Select one or more destination timezones from the dropdown. The tool calculates the equivalent time in each selected zone, accounting for UTC offsets.
- Account for DST: The tool uses IANA timezone database rules to handle Daylight Saving Time transitions automatically. Check the DST indicator to verify if summer/winter time affects your conversion.
Technical Details
Timezones are defined as offsets from UTC (Coordinated Universal Time), ranging from UTC-12 to UTC+14. The IANA Time Zone Database (tzdata) maintains rules for each named zone, including historical changes and DST transitions. Zone names follow the "Area/Location" format (America/New_York, Europe/London, Asia/Tokyo).
Daylight Saving Time (DST) complicates conversions—not all zones observe it, and transition dates vary by country. The EU transitions on the last Sunday of March/October; the US on the second Sunday of March and first Sunday of November. Some zones have unusual offsets: Nepal is UTC+5:45, India is UTC+5:30. JavaScript's Intl API provides access to the system's tzdata for accurate conversions. Always store times in UTC and convert to local only for display.
Common Mistakes to Avoid
- Using Fixed Offsets Instead of Zone Names: "UTC+5" ignores DST changes; "America/New_York" applies correct rules year-round. Always use IANA zone names (Asia/Kolkata, not "IST" which is ambiguous—Ireland, Israel, and India all use "IST").
- Forgetting DST Transitions: Meetings scheduled during DST transitions may shift unexpectedly. A 2 PM meeting in March might become 3 PM after "spring forward." Always verify both sides of the conversion around transition dates.
- Assuming Timezones Are Whole Hours: Many zones use 30 or 45-minute offsets (India: +5:30, Nepal: +5:45, Iran: +3:30). Don't truncate to whole hours when calculating offsets or displaying times.
Related Tools
Working with Unix timestamps instead of human-readable times? Use our Unix Timestamp Converter to convert between formats. For quick UTC-to-local conversions, try the UTC/Local Converter.
Frequently Asked Questions
What's the difference between UTC and GMT?
Functionally identical for most purposes—both represent the time at 0° longitude. UTC is the modern standard based on atomic clocks, while GMT is the older astronomical standard. Use UTC in technical contexts; GMT is colloquial.
Why do some countries have half-hour timezone offsets?
Historical, political, and geographical reasons. India chose UTC+5:30 to be offset from both Pakistan (+5) and Bangladesh (+6). Nepal's +5:45 maintains distinction from India. These offsets are valid and must be handled correctly.
How do I schedule a meeting across multiple timezones?
Pick a time that falls within business hours for all participants, typically 9 AM to 6 PM local. Enter the meeting time in one timezone, then check the converted times in other zones. A 9 AM meeting in New York is 2 PM London, 6:30 PM Mumbai, and 10 PM Tokyo.