How are timezones kept accurate?

We use the browser's native Intl.DateTimeFormat with IANA timezone identifiers. It automatically handles daylight saving rules maintained by the tzdata database.

Can I save my city list?

Yes — your selected cities are saved to browser localStorage, so they persist between visits.

World Clock

Date & Time· 11 tools

Free world clock to view current time in multiple cities simultaneously. Choose from a preset list of major global cities or add any IANA timezone. Automatically handles daylight saving transitions.

Your local timezone: UTC

New York

America/New_York · UTC-04:00

17:43:00

Mon, Jun 22

London

Europe/London · UTC+01:00

22:43:00

Mon, Jun 22

Tokyo

Asia/Tokyo · UTC+09:00

06:43:00

Tue, Jun 23

Sydney

Australia/Sydney · UTC+10:00

07:43:00

Tue, Jun 23

Frequently Asked Questions

References

IANA Time Zone Database — Internet Assigned Numbers Authority

Related Tools

Timezone Converter
Convert a date and time between any two IANA timezones with DST handling built in.
Online Stopwatch & Timer
Millisecond-accurate online stopwatch with lap splits and countdown timer mode. Keeps running in background tabs. Free, no signup, any device.
Age in Days Calculator
Calculate exact age in days, hours, minutes, and seconds — plus life milestones countdown.

Frequently Asked Questions

References and sources

Related Tools