World Time Zones - Persian Numerals

Input: Compare New York (EST, UTC−5) and London (GMT, UTC+0) at 2 PM London time

Result: New York: 9:00 AM EST. Time difference: 5 hours. Overlapping work hours (9 AM–5 PM local): 2 PM–5 PM London / 9 AM–12 PM New York.

How many time zones are available?

The tool covers all IANA time zones — over 400 zones representing every country and region worldwide, including zones that observe Daylight Saving Time.

Does the world time tool handle Daylight Saving Time?

Yes. The tool automatically adjusts for Daylight Saving Time based on the current date and each zone's DST rules.

Why does my city show a different time than my local clock?

The most common cause is that your device's time zone setting does not match the IANA time zone for your region. For example, India has one IANA zone (Asia/Kolkata, UTC+5:30) but some devices are set to a generic UTC+5:30 offset without the IANA label. Another cause: if you are in a region with disputed or recently changed time zone rules (like certain Mexican states that abolished DST in 2022), the IANA database may not yet reflect the change on older devices.

What is the best meeting time between New York and London?

With standard 9 AM–5 PM work hours in both cities, the overlap window is 9 AM–12 PM New York time (2 PM–5 PM London time), giving you a 3-hour window. This holds in both summer and winter because the 5-hour offset stays constant — New York shifts from EST (UTC−5) to EDT (UTC−4) and London shifts from GMT (UTC+0) to BST (UTC+1) at nearly the same time each year. The Planner tab on this page shows this overlap automatically once you add both cities, and you can adjust the work-hours window if your team starts earlier or later.

What is the best meeting time between London and Dubai?

Dubai does not observe Daylight Saving Time, so the overlap shifts with the seasons. In summer (when London is on BST, UTC+1), the overlap is 9 AM–2 PM London time (12 PM–5 PM Dubai time) — a 5-hour window. In winter (when London is on GMT, UTC+0), it narrows to 9 AM–1 PM London time (1 PM–5 PM Dubai time) — a 4-hour window. The Planner tab accounts for this automatically by computing each city's actual UTC offset for the date you select, so you always see the correct overlap regardless of season.

What is the best meeting time between New York and Tokyo?

There is no overlap between standard 9 AM–5 PM work hours in New York and Tokyo. Tokyo is 13–14 hours ahead of New York (depending on DST), so when it is 9 AM in New York it is already 10–11 PM in Tokyo. For teams split across this gap, the most workable approaches are: rotate the meeting time so the inconvenience alternates rather than always falling on one side; use asynchronous updates (recorded video briefs or shared documents) instead of live meetings; or schedule two shorter check-ins at the edges — one at 8 AM New York / 11 PM Tokyo for the Tokyo side to join from home, and one at 7 PM New York / 8–9 AM Tokyo for the New York side to take in the evening. The Planner tab shows partial overlap suggestions when no full overlap exists, so you can see which hours come closest.

What should I do when there is no overlapping work hours between time zones?

Not every city pair has a workable live-meeting window — New York and Tokyo, or Los Angeles and Mumbai, have zero overlap during standard 9–5 hours. The honest approach is to accept this and design around it rather than forcing someone to take a 2 AM call every week. Three strategies work in practice: (1) rotate the meeting time so the burden alternates between teams rather than always falling on the same side; (2) replace the live meeting with asynchronous updates — a recorded video summary, a shared document, or a written standup that each team reviews during their own work hours; (3) if a live meeting is truly necessary, schedule it at the least-bad time and keep it short (15–20 minutes). The Planner tab shows partial overlap suggestions ranked by how many cities are in work hours, so you can find the least disruptive option.

How does daylight saving time affect meeting planning across time zones?

Daylight Saving Time shifts a city's UTC offset by one hour on transition dates, and different countries transition on different dates — the US shifts in mid-March and early November, while Europe shifts in late March and late October. This means the gap between two cities can change by 1–2 hours twice a year. For example, London and Dubai have a 3-hour difference in summer but a 4-hour difference in winter because Dubai does not observe DST. Tools that use fixed UTC offsets (like "UTC+4" hardcoded) will be wrong for half the year. This tool computes each city's actual offset for the specific date you select using the IANA timezone database, so the Planner tab always reflects the correct overlap — even on the day of a DST transition.

How do I share a meeting time with people in different time zones without confusion?

The Planner tab has a Copy Summary button that copies a plain-text breakdown of the best meeting times to your clipboard, showing each city's local time side by side. You can paste it directly into an email, Slack, or WhatsApp message. For example, it produces something like: "Best meeting times (all cities in work hours): London 9 AM / Dubai 12 PM, London 10 AM / Dubai 1 PM, London 11 AM / Dubai 2 PM." This eliminates the back-and-forth of "what time is that for you?" because every participant sees their own local time in the same message.

How do I compare time zones side by side?

Add two or more cities using the Add button and switch to the Timeline or Grid view. The Timeline view shows a 24-hour bar for each city with the current time highlighted, so you can see at a glance what hour it is in each place. The Grid view shows a compact table of all selected cities with their current local times and analog clocks. The Difference view shows the hour offset between each pair of cities. You can add up to six cities simultaneously.

Can I check what time it will be in another city on a future date?

Yes. Use the date picker or the timeline scrubber to move to any past or future date. The tool recalculates every city's local time for that date, including any DST transitions that occur between now and then. This is useful for scheduling meetings days or weeks ahead, since the UTC offset for some cities changes on DST transition dates.

What is the difference between the Timeline, Grid, Difference, and Planner views?

Timeline shows a 24-hour horizontal bar for each city with work-hours shading, so you can visually scan for overlap. Grid shows a compact table with each city's current time and an analog clock. Difference shows the hour offset between every pair of selected cities. Planner computes the best meeting times by finding hours where all selected cities are within your configurable work-hours window, and ranks them by how many cities are in work hours.

How accurate are the time zone offsets?

All offsets are computed from the IANA timezone database (also called the tz database), which is the same source used by operating systems, programming languages, and major scheduling platforms. The database is updated several times per year as governments change DST rules or time zone boundaries. This tool uses the browser's Intl API, which relies on the device's bundled IANA data, so the accuracy depends on your device being reasonably up to date. For critical scheduling, always confirm the time with participants directly.

Can I use this world clock for free without signing up?

Yes. The tool is entirely free, requires no account, no sign-up, and no app install. It runs in your browser and your selected cities are saved locally on your device. Nothing is sent to any server.

How do Persian numerals differ from Arabic numerals?

The most visible differences are in the digits 4, 5, and 6. Persian 4 (۴) looks like a small triangle, while Arabic 4 (٤) is more angular. Persian 5 (۵) looks like a small heart shape, while Arabic 5 (٥) is a circle. Persian 6 (۶) resembles a reversed 9, while Arabic 6 (٦) is a single dot above the line. If you are working with documents from Iran or Afghanistan, use the Persian mode. For documents from Egypt, Saudi Arabia, or the UAE, use the Arabic mode.