FAQ

Frequently asked questions

Short, honest answers about where the time comes from and what we do with your data. For longer explanations, read the guides.

How accurate is the time shown on ExactTime?

The clock is redrawn every second, but its accuracy comes from your own device's system clock. If your phone or computer keeps automatic network time synchronisation switched on, it is typically within a fraction of a second of official time. If that setting is off, or the clock was set by hand, every city on the page will be off by the same amount. ExactTime does not correct your device clock and does not claim to be an official time source.

Why does the time here differ from the time on my phone?

Almost always because the two devices are not equally well synchronised, or because they are set to different time zones. Compare the zone name shown under the main clock with the zone configured in your phone's date and time settings. A difference of exactly one hour usually means a daylight saving setting or an outdated time zone rule on one of the devices; a difference of a few seconds means one clock has drifted.

What is my time zone, and how does the site know it?

Your browser reports an IANA time zone identifier — something like Europe/Paris or America/Chicago — which ExactTime reads through the standard Intl API. No location permission is required for this: the identifier comes from your device settings, not from GPS. If it looks wrong, change the time zone in your operating system settings and reload the page.

How is daylight saving time handled?

Automatically. Each city is stored as a time zone identifier rather than a fixed offset, so the offset is derived for the exact instant being shown, using the IANA time zone database that ships with your device and browser. On the days clocks shift, the displayed time shifts with them. Our guide on how daylight saving time works explains the mechanics in detail.

Do you store my location?

No. Sunrise and sunset are only calculated if you press the button asking for your location, your browser then asks your permission, and the coordinates are used in your browser to run the calculation. They are not sent to us, not written to a database, and not shared with advertising partners.

Why is the sunrise or sunset missing for my location?

Above the Arctic Circle and below the Antarctic Circle there are periods when the sun does not rise or does not set at all. In those cases the panel says so rather than inventing a time.

Can I use ExactTime for legal, aviation, medical or financial timing?

No. The site is a convenience reference. For anything where a second of error carries legal, safety or financial consequences, use an authoritative source such as your national time institute or a certified time service. See our disclaimer.

Why do some cities show the same offset but different names?

Because offsets are not identities. Several zones share an offset today and diverge later in the year when only some of them observe daylight saving. That is exactly why the site tracks zone identifiers rather than plain offsets, and why time zone abbreviations like CST are ambiguous.

Does ExactTime use cookies or show ads?

The site itself stores small preference values in your browser's local storage — your chosen city, your theme, and your cookie choice. Advertising is how the site stays free; advertising cookies are only enabled after you accept them in the consent banner. Full detail, including how to opt out of personalised advertising, is in the Privacy Policy.

Is the city list complete, and can I request an addition?

The directory covers well over two hundred cities across every inhabited zone, and we add more on request. Email us the city and country and we will include it if a distinct IANA zone applies.

Question not answered here? Email hbatchi2002@gmail.com or use the contact form.