What Is a Time Zone Calculator?
This calculator converts a time from one UTC offset to another — useful for scheduling calls, meetings, or events across different time zones, without needing to manually calculate the hour difference.
How to Use the Time Zone Calculator
- Enter the time you want to convert.
- Enter the source time zone's UTC offset (e.g., UTC-5 for US Eastern Standard Time).
- Enter the target time zone's UTC offset.
- View the converted time instantly.
Time Zone Conversion Formula
Common UTC Offsets Reference
| Time Zone | Standard UTC Offset |
|---|---|
| US Eastern (EST) | UTC−5 |
| US Central (CST) | UTC−6 |
| US Pacific (PST) | UTC−8 |
| UK (GMT) | UTC+0 |
| Central Europe (CET) | UTC+1 |
| India (IST) | UTC+5:30 |
| Japan (JST) | UTC+9 |
Note: many regions observe daylight saving time, which shifts the offset by an hour for part of the year — verify the current offset for your specific dates.
Worked Example
Offset difference: 0 − (−5) = +5 hours
Converted time: 2:00 PM + 5 hours = 7:00 PM UTC
Common Mistakes to Avoid
- Forgetting daylight saving time adjustments, which shift many regions' offsets for part of the year.
- Mixing up which direction is "ahead" or "behind" — a higher (more positive) UTC offset means that time zone is ahead of a lower one.
- Not accounting for the date changing when converting near midnight across a large time difference.
Frequently Asked Questions
Find the difference between the two time zones' UTC offsets, then add or subtract that difference from the original time.
It's the number of hours a time zone is ahead of or behind Coordinated Universal Time (UTC), the global time reference standard.
No — enter the current UTC offset for your specific dates, since offsets can shift by an hour during daylight saving time periods in many regions.
A few regions, like India (UTC+5:30) and parts of Australia, use half-hour offsets rather than whole-hour offsets, for historical and geographic reasons.
If the time shift crosses midnight (either forward or backward), the date will change — check the resulting hour to see if it wrapped past midnight.