Time Zone Converter
Free time zone converter. Compare current times across three zones and find the working-hours overlap for a meeting. No signup.
What the time zone converter does
It shows the current time in up to three time zones at once and works out the window when everyone’s working day overlaps, assuming a 9am–5pm schedule in each zone. That overlap is the practical question behind most scheduling: not what time it is, but what time you can actually all meet. Daylight saving is handled automatically by your browser’s time-zone database.
How it works
- Each selected zone’s current time and date is calculated from your device clock and the zone database.
- The overlap search tests each hour of the day and returns the first hour when every selected zone is between 9am and 5pm local time.
- If no such hour exists — common when zones are half a world apart — the tool reports no 9–5 overlap, and you have to compromise on an early or late call.
A worked example
New York and London during winter, when New York is UTC−5 and London is UTC+0:
| New York (EST) | London (GMT) | Both in work hours? |
|---|---|---|
| 8:00 | 13:00 | No — NY before 9 |
| 9:00 | 14:00 | Yes — overlap starts |
| 12:00 | 17:00 | Yes — overlap ends |
| 13:00 | 18:00 | No — London after 5 |
The overlap is 9:00–12:00 in New York, or 14:00–17:00 in London — a three-hour window. Add Sydney, which is 15 hours ahead of New York, and 9am in New York is midnight in Sydney, so no 9–5 overlap exists.
Standard time offsets
| Zone | Standard offset |
|---|---|
| Los Angeles | UTC−8 |
| Chicago | UTC−6 |
| New York | UTC−5 |
| London | UTC+0 |
| Paris / Berlin | UTC+1 |
| Dubai | UTC+4 |
| Mumbai | UTC+5:30 |
| Singapore | UTC+8 |
| Tokyo | UTC+9 |
| Sydney | UTC+10 |
| Auckland | UTC+12 |
Most of these shift by an hour during daylight saving, and some regions do not observe it at all. The offsets above are the standard-time values.
Common mistakes
- Forgetting daylight saving. Offsets can change twice a year, and different countries switch on different dates. The tool uses the browser database, which accounts for that.
- Assuming a whole number of hours. India, for example, is UTC+5:30, so some zones differ by half hours.
- Scheduling across the date line. When the overlap falls on different calendar days, the date matters as much as the time.
- Using the tool as the record of a meeting. It converts and shows overlaps; confirmation still belongs in a calendar invite with the zone attached.
Scheduling across three zones
Adding a third zone usually shrinks the overlap or removes it. New York and London share a comfortable three-hour window, but Sydney is 15 hours ahead of New York, so the whole of New York’s working day falls in Sydney’s night. In cases like that, no single hour suits everyone, and the fair answer is to rotate the meeting time — early for one region one week, late for the other the next — rather than leaving the same people inconvenienced every time. When a zone is only an hour or two outside the overlap, a slightly early or late start is usually better than forcing a bad slot on everyone.
Frequently asked questions
Why is there no overlap for some zone combinations?
Because the working days barely touch. When the time difference exceeds about eight hours, one party has to meet outside 9–5. Find the least-bad hour rather than a perfect one.
Does it account for daylight saving?
Yes — it relies on the browser’s time-zone database, which includes DST rules, so the current-time display and the overlap follow the seasons automatically.
How do I count working days between dates?
That is a different question. The business days calculator counts weekdays between two dates, and the age calculator handles plain calendar-date differences.