Time Zone Converter
See the time in several cities at once and spot a slot that works for everyone. Green is working hours (9am–5pm), yellow is possible, and grey is outside reasonable hours.
New York
12:09:58 PM
Sat, Oct 3
London
05:09:58 PM
Sat, Oct 3
Tokyo
01:09:58 AM
Sun, Oct 4
Sydney
03:09:58 AM
Sun, Oct 4
Meeting Time Finder
Compare multiple time zones to find the best meeting times. Green indicates ideal working hours (9am-5pm), yellow shows possible times (7-9am or 5-8pm), and gray means outside reasonable hours.
Convert Time
New York (EST/EDT)
Saturday, October 3, 2026 at 12:09 PM
London (GMT/BST)
Saturday, October 3, 2026 at 05:09 PM
UTC Reference
Saturday, October 3, 2026 at 04:09 PM
Clocks change on different dates in the US and Europe, so the gap between them can shift by an hour for a few weeks each year.
How Time Zones Work Around the World
Time zones are essential for coordinating time across different regions of the world. They ensure that people in different countries can maintain consistent schedules based on the position of the sun.
What Are Time Zones?
A time zone is a region of the Earth that uses the same standard time. Because the Earth rotates 360 degrees every 24 hours, it is divided into 24 time zones, each roughly 15 degrees of longitude apart.
The starting point for all time zones is the Prime Meridian, located in Greenwich, which defines 0° longitude.
Coordinated Universal Time (UTC)
The global standard for timekeeping is Coordinated Universal Time (UTC). All time zones are measured as offsets from UTC (e.g., UTC+1, UTC-5).
UTC replaced older systems like Greenwich Mean Time (GMT) and is based on highly precise atomic clocks.
Major World Time Zones
Why Time Zones Are Important
Travel and Aviation
Scheduling flights across countries
Global Business
Coordinating meetings across regions
Technology
Synchronizing servers and networks
Communication
Managing international calls and events
Compare current times across world time zones — essential for scheduling international meetings, calls, and travel.
Formula
UTC ± offset. Add or subtract the difference between two zone offsets to convert.
Reference Values
- •UTC+0 = London (GMT)
- •UTC-5 = New York (EST)
- •UTC+9 = Tokyo (JST)
Related tools
FAQ
Common questions about Time Zone Converter
How we calculate this
Time zone offsets come from the IANA Time Zone Database. Source: IANA Time Zone Database.
Spotted a mistake? Tell us and we'll check it within a few days. See how we check our calculators.