Time zone rules, including daylight saving changes, come from your browser, so the clocks stay correct all year. Your list of cities is saved on this device for next time.
Frequently asked questions
Does the world clock handle daylight saving time?
Yes. It uses the official time zone database built into your browser, which includes daylight saving rules for every region.
Can I plan a meeting across time zones?
Yes. The ahead/behind labels show the gap at a glance, so you can find hours that fall inside the working day for everyone.
Is TimerTab free?
Yes. Every clock, timer and alarm is free, with no account and no download. It works in any modern browser on desktop, phone or tablet.
Will it keep time if I switch tabs?
Yes. TimerTab counts from the real clock time instead of counting ticks, so it stays accurate when the tab is in the background and catches up instantly when you come back.
Does it work offline?
Yes. After your first visit the pages are cached on your device, so timers, the stopwatch and alarms keep working without an internet connection.