Time Zone Converter
Compare times across 21 major cities with live clocks and an hour-by-hour table — DST handled exactly, everything runs in your browser.
Timezone math uses the browser's own IANA database, so daylight-saving shifts are exact — no network involved.
This tool runs entirely in your browser. Your data never leaves your device — it is not uploaded to any server.
How to use
- 1Choose the starting city — its live local clock appears underneath.
- 2Choose the destination city; the clock and UTC offset update instantly.
- 3Scan the hour-by-hour table to find times that work for both sides.
- 4Use the swap button to flip the two cities.
Time Zone Converter
Pick any two cities from Los Angeles to Tokyo and see both live clocks side by side, the exact offset difference for today, and a 24-row comparison table showing what every hour of the day becomes in the other city — the fastest way to find a meeting slot across time zones.
The conversion uses your browser's built-in IANA time zone database, so daylight-saving transitions land on the correct minute without any network call.
Frequently asked questions
Does the converter handle daylight saving time?
Yes. Offsets are computed with the browser's own IANA time zone rules for today's date, so a city currently on DST shows its correct shifted offset and the hour table reflects the real clocks on both sides.
Why does the hour table show a different date in some rows?
When cities are far apart, one side's calendar date changes during the day. Each row shows the destination's date next to the time so you can spot when, for example, 9:00 in Shanghai is still 21:00 the previous evening in New York.
Does this tool need internet access?
No. City times come from the time zone database built into your browser and your device clock — nothing is downloaded and no location is shared.
Related tools
Unix Timestamp Converter
Convert Unix seconds or milliseconds to human dates and back, with a live clock, local-timezone and UTC output — all in your browser.
All tools →
Time Unit Converter
Seconds, minutes, hours, days, weeks, months and years — with the month/year caveat explained.
All tools →
Date Calculator
Days between two dates in years, months and days — or add and subtract days from any date — with leap years handled exactly.
All tools →
Age Calculator
Work out an exact age in years, months and days, total days lived, and a live countdown to the next birthday — calendar accurate.
All tools →
Embed this tool
Put this tool on your own site with one line — it runs entirely in the visitor's browser.
<iframe src="https://zoyku.com/en/tools/timezone-converter?embed=1" width="100%" height="640" style="border:0;border-radius:16px" title="Zoyku — timezone-converter" loading="lazy"></iframe>