The Complete Guide to Time Conversion
Converting time between timezones is a daily necessity for remote workers, travelers, and global teams. Here's everything you need to know.
Understanding UTC Offsets
UTC offsets describe how far a timezone is from Coordinated Universal Time: - **UTC-5**: 5 hours behind UTC (US Eastern Standard Time) - **UTC+5:30**: 5.5 hours ahead of UTC (India Standard Time) - **UTC+0**: Same as UTC (GMT, London in winter)
To convert: add or subtract the offset from UTC time.
Common Timezone Conversions
| City | Timezone | UTC Offset | |------|----------|------------| | New York | EST/EDT | -5/-4 | | London | GMT/BST | 0/+1 | | Paris | CET/CEST | +1/+2 | | Dubai | GST | +4 | | Mumbai | IST | +5:30 | | Singapore | SGT | +8 | | Tokyo | JST | +9 | | Sydney | AEST/AEDT | +10/+11 |
How Daylight Saving Changes Things
When DST is in effect, many regions shift by +1 hour. This means the UTC offset changes seasonally. For example: - New York: UTC-5 (winter) → UTC-4 (summer) - London: UTC+0 (winter) → UTC+1 (summer)
This makes fixed timezone conversions unreliable — always check whether DST is active.
Quick Mental Math Tricks
**New York to London**: Add 5 hours (winter) or 4 hours (summer) **New York to Tokyo**: Add 14 hours (winter) **London to Singapore**: Add 8 hours **New York to LA**: Subtract 3 hours
Use a Converter for Accuracy
Mental math is error-prone. For important scheduling, always use a timezone converter. Our [Timezone Converter](/timezone-converter) handles all DST transitions automatically.
When in doubt, express times in UTC to avoid confusion entirely.
