World Clock Comparator
Compare current times across multiple cities worldwide side by side.
Reviewed by the ToolNestr Editorial Team — July 2026
Select up to 6 cities. Click a city in the dropdown or type to filter.
No cities added yet
Search and add cities above to compare times.
How the world clock comparator works
The world clock comparator displays the current time simultaneously for every city you add. Each city card shows the local time down to the second, the current date, the UTC offset, and whether daylight saving time (DST) is currently in effect. A 24-hour horizontal timeline sits below each city, with the 9 AM to 5 PM business hours highlighted in green and a red marker indicating the current local time position. This layout makes it instantly clear which cities share overlapping working hours at a glance.
Three cities at 14:32 UTC showing their local times and business hour overlaps
Why use a world clock comparator?
Time zone differences are one of the biggest challenges in global communication. When you manage a remote team spread across continents, knowing the current time in each location is not enough — you need to understand how those times relate to each other. A world clock comparator solves this by showing every city on the same visual axis. The 24-hour timeline with business hours highlighting reveals overlaps at a glance. If London is at 14:00 and New York is at 09:00, you can immediately see they share four hours of working time. The same visual logic applies to any set of cities.
Common use cases
Remote team stand-ups
Find a daily stand-up time that works for engineers in San Francisco, London, and Bangalore. The overlap view shows which hours are viable for everyone without requiring anyone to join before 6 AM or after 10 PM.
Travel planning
When traveling, keep track of home time versus destination time. Avoid calling family and friends at 3 AM their time by checking the comparator before dialing.
Global event scheduling
Schedule webinars, gaming sessions, or live streams that accommodate audiences across the Americas, Europe, and Asia-Pacific. The green overlap zone tells you exactly when to go live.
Financial market tracking
Track the opening hours of stock exchanges in New York, London, Tokyo, and Hong Kong. See when trading sessions overlap for maximum liquidity periods.
Understanding timezone offsets
Timezone offsets are expressed as the difference from Coordinated Universal Time (UTC). A location at UTC+5 is five hours ahead of UTC, meaning when it is noon UTC, it is 5 PM there. Offsets can be positive (east of the prime meridian) or negative (west). Daylight saving time adds further complexity. During DST, clocks are set forward by one hour, effectively changing the offset. For example, New York shifts from UTC-5 (EST) in winter to UTC-4 (EDT) in summer. The world clock comparator uses the browser native Intl API, which queries the latest IANA timezone database on your device, so DST transitions are applied automatically and accurately.
Offset examples
Tips for using the comparator
Focus on the green zone
The green highlighted section on each timeline represents 9 AM to 5 PM local business hours. Wherever green bars overlap across cities, that is the window where meetings are most likely to work. The red marker shows the current time so you can see where you are right now relative to everyone else working day.
Watch for half-hour offsets
Not all timezones use whole-hour offsets. India (UTC+5:30), Nepal (UTC+5:45), Iran (UTC+3:30), and Newfoundland (UTC-3:30) are common examples. The Intl API handles these correctly, but be mindful when doing mental math.
DST changes shift the timeline
When a city enters or exits DST, its offset changes by one hour. This shifts the entire timeline relative to UTC. The comparator updates automatically, but if you are planning a meeting weeks ahead, check the expected DST transition dates for the relevant cities.
Add cities strategically
Start with cities that are most important to your schedule, then add others to find the common overlap. If you are comparing across six cities and the overlap is tiny or nonexistent, consider removing the least flexible participant or rotating the meeting time.
Limitations to be aware of
While the world clock comparator is a powerful visualization tool, it has some limits. First, the 9 AM–5 PM default business hours are a Western convention and may not reflect local working customs in many parts of the world. In Spain, businesses often break for lunch from 2 PM to 4 PM. In Japan, the workday commonly starts earlier and includes overtime culture. In the Middle East, the workweek runs Sunday through Thursday. The tool does not account for these cultural variations. Second, the tool cannot factor in lunch breaks or individual availability. Someone may appear available based on business hours but be in a meeting or on leave. Third, the accuracy depends on the IANA timezone data shipped with the user browser. While this is generally reliable, it may lag behind last-minute government DST changes. For the most current data, ensure your operating system is up to date.
How to use the comparator effectively
Add cities
Type to search from 50+ worldwide cities. Add up to 6 cities that matter to your schedule.
Read the cards
Each card shows the current time, date, UTC offset, DST status, and a 24-hour timeline.
Find overlap
Look for green zones that align across cities. That is your window for meetings and calls.
Business hours by region reference
| Region | Local Business Hours | UTC Equivalent |
|---|---|---|
| US East Coast | 9 AM – 5 PM ET | 13:00 – 21:00 UTC (winter) / 12:00 – 20:00 UTC (summer) |
| US West Coast | 9 AM – 5 PM PT | 17:00 – 01:00 UTC (winter) / 16:00 – 00:00 UTC (summer) |
| Western Europe | 9 AM – 5 PM CET/CEST | 08:00 – 16:00 UTC (winter) / 07:00 – 15:00 UTC (summer) |
| United Kingdom | 9 AM – 5 PM GMT/BST | 09:00 – 17:00 UTC (winter) / 08:00 – 16:00 UTC (summer) |
| India | 9 AM – 5 PM IST | 03:30 – 11:30 UTC |
| China / Singapore | 9 AM – 5 PM CST/SGT | 01:00 – 09:00 UTC |
| Japan / Korea | 9 AM – 5 PM JST/KST | 00:00 – 08:00 UTC |
| Australia East | 9 AM – 5 PM AEST/AEDT | 23:00 – 07:00 UTC (winter) / 22:00 – 06:00 UTC (summer) |
| New Zealand | 9 AM – 5 PM NZST/NZDT | 21:00 – 05:00 UTC (winter) / 20:00 – 04:00 UTC (summer) |
Related tools
Frequently asked questions
How many cities can I compare?
Up to 6 cities at once. Add and remove cities freely from a predefined list of 50+ major world cities.
How do I see business hours overlap?
Each city has a 24-hour bar showing 9 AM–5 PM highlighted in green, making it easy to see overlapping work hours.
How accurate are the timezones?
They use the browser's Intl API for current IANA timezone data, accounting for DST.
Does it auto-refresh?
Yes — times update every 10 seconds to keep current.