World clock — real-time current time across major global cities
Show the current time across multiple cities live, side by side. Pin one city's time as the base and the rest update to the matching local time. Cities can be added or removed freely.
How to use
Type a city name in the add form and click Add — a card with that city's current time appears. Click Make base on any card to switch to pinned mode: the rest of the cards show the matching local times. You can edit the base time manually (e.g. what's New York 18:00 in Tokyo?) and use Back to live to return to the real-time view.
FAQ
- Where does the city data come from?
- The IANA timezone list via Intl.supportedValuesOf("timeZone"), fetched once from the browser — no server.
- Are my searches uploaded?
- No, search runs purely in your browser.
- Is the city list saved?
- Yes, in localStorage on your device. It's restored on next visit and never leaves your device.
- Does it handle daylight saving?
- Yes, DST rules are applied automatically per timezone.
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