A Beautiful Timezone Converter and World Clock for Teams

A timezone converter shows what a selected date and time in one city becomes in other cities. Horizon Clock also places those converted times beside live world clocks, so you can see day changes and compare a whole team at once.

Select Convert a time, choose the city the time belongs to, then enter the date and local time. Every clock you have added updates to show that same moment in its own timezone, with a marker when it falls on the previous or next day. The Now button returns everything to the live current time.

Yes. Add as many cities as you need and they all convert together. The layout stays usable with a dozen or more clocks on a normal desktop, and there is a generous upper limit only to keep the page responsive.

Yes. Horizon Clock uses the IANA timezone data built into your browser through the Intl API, which applies the correct offset for the specific date you select. Transitions like the ones in New York, London, or Sydney are calculated for you, within the timezone data your browser provides.

Because cities far apart can sit on different calendar dates at the same moment. Converting only the hour can be misleading, so Horizon Clock shows the full date for every city and adds a Next day or Prev day marker whenever the converted moment crosses midnight relative to the source city.

Yes. Add each teammate's city, then either slide the quick planning bar or convert a specific proposed time. All clocks move together, so you can see at a glance who would be in normal working hours, early morning, or late evening.

Yes. Copy share link produces one compact URL that carries your cities, custom labels, clock order, time format, and an exact converted time if you set one. Opening it shows a preview first, so it never silently overwrites the other person's own saved setup.

Horizon Clock does not request GPS or precise-location permission. It reads the default timezone reported by your browser to suggest a starting clock, and you can replace or remove it. Your selected clocks and settings are stored locally in your browser.

No. The day and night colors, the sun and moon arc, and the small skylines are an illustrative, calming design generated from each city's local time. They are not astronomical sunrise or sunset calculations and do not show real weather or real buildings.

Yes. Horizon Clock is completely free, with no account, no sign-up, and no watermark. It is made by Calipzo, whose main product turns a Google Sheets content calendar into a client review portal.

Up to 50, which is far more than most teams need. The interface is optimized to stay smooth with many clocks, and share links are validated and bounded so oversized or malformed links are rejected safely.