Time Zone Difference Calculator — Compare Time Zones
Calculate the time difference between any two time zones and see the current time in both. Useful for scheduling international calls and meetings. See also our Time Zone Converter and Time Calculator.
How to Calculate Time Zone Differences
- Select the first time zone from the dropdown.
- Select the second time zone.
- Click Calculate to see the hour difference.
- View the current time in both zones.
- Use this to schedule calls or meetings across time zones.
Formula
Time Difference = UTC Offset of Zone 2 - UTC Offset of Zone 1
Time in Zone = UTC Time + Zone Offset
Example: EST (UTC-5) to IST (UTC+5:30) = 10.5 hours
Example
Zone 1: Eastern Time (UTC-5)
Zone 2: India Standard Time (UTC+5:30)
Difference = 5.30 - (-5) = +10.5 hours
When it is 9:00 AM in New York, it is 7:30 PM in India
Common Time Zone Differences
| From | To | Difference |
|---|---|---|
| New York (EST) | London (GMT) | +5 hours |
| New York (EST) | Tokyo (JST) | +14 hours |
| London (GMT) | Dubai (GST) | +4 hours |
| Los Angeles (PST) | New York (EST) | +3 hours |
| New York (EST) | India (IST) | +10.5 hours |
| London (GMT) | Sydney (AEST) | +10 hours |
Frequently Asked Questions
Does this account for Daylight Saving Time?
This calculator uses standard UTC offsets. During DST, some zones shift by 1 hour. Check if your region observes DST and adjust accordingly.
Why are some time zones offset by 30 minutes?
Some countries chose half-hour offsets to better align with solar noon. India (UTC+5:30), Nepal (UTC+5:45), and Iran (UTC+3:30) are examples.
What is UTC?
UTC (Coordinated Universal Time) is the primary time standard. All time zones are defined as offsets from UTC, ranging from UTC-12 to UTC+14.
Can the difference be more than 24 hours?
The maximum difference between any two time zones is 26 hours (UTC-12 to UTC+14). Most practical differences are within 12 hours.
How do I schedule a meeting across time zones?
Find the time difference, then look for overlapping business hours (typically 9 AM - 5 PM) in both zones. For large differences, one party may need to adjust.