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Time Zone Converter & World Clock

Select a base time and cities to see local times around the world at a glance. Daylight saving time is handled automatically — great for scheduling meetings across time zones.

Last updated: 2026/10/16 Utility Feedback & bug reports
Base
A note about daylight saving time (DST)Many regions observe daylight saving time from spring to autumn, shifting their offset by one hour. This tool applies each region's DST rules automatically, but when you schedule meetings around switch-over dates (roughly March and November, or October and April in the Southern Hemisphere) always double-check the actual local time on the day. Cities marked with a "DST" badge are observing daylight saving time on the displayed date.

Meeting Planner

A side-by-side grid that maps one day (0:00–23:00) of your base time zone against the local time of every selected city. Colors show working hours at a glance, so you can find a meeting time that works for everyone. Click any cell to set that moment as the base date & time.

Working hours (9–18) Early / late (7–9, 18–22) Overnight (22–7)

How to Use

1

Set the base time

Choose a base time zone and date/time. By default it follows your current local time in real time.

2

Add cities

Use the "Add a city" menu to add the cities you want to compare, such as Tokyo, New York and London.

3

Check local times

Each city shows its local time, UTC offset and day difference (prev/next day). Use "Copy list" to share the results.

About the Time Zone Converter & World Clock

This web tool lets you pick a base date/time and several cities to view their local times side by side. It uses the browser's Intl.DateTimeFormat API, so daylight saving time (DST) transitions are applied automatically according to each region's rules. Use it to schedule online meetings with overseas teams, check time differences before travel, build a quick reference of start times across the globe for streams and events, and more. Everything runs in your browser — your dates and settings are never sent to any server.

Alongside time zone conversion, use the Unix Timestamp Converter to turn epoch seconds into a date, the Date Calculator to count days between two dates, and the Day of the Week Calculator to find the weekday of any date. For the fundamentals of time zones, UTC and DST, read our guide to time zone basics.

Features

  • Real-time world clockLive local time for each city updated every second — use it as a world clock.
  • Automatic DST handlingDaylight saving rules are applied automatically via Intl.DateTimeFormat. No manual adjustment needed.
  • Meeting plannerSet a base time and instantly see each city's local time and day offset at that moment.
  • Privacy firstAll calculations run in your browser. Your dates and settings are never sent to a server.

Use Cases

  • Scheduling online meetings with overseas offices and clients
  • Checking local times and offsets before travel
  • Announcing start times of streams and events across countries
  • Finding a good time to call family and friends abroad
  • Tracking trading hours of overseas stock and forex markets

FAQ

Is daylight saving time handled correctly?
Yes. The tool uses the browser's built-in Intl.DateTimeFormat API, which applies each region's daylight saving time (DST) rules automatically. The correct offset is shown depending on whether the selected date falls within the DST period.
Are my dates and selected cities sent to a server?
No. All calculations happen entirely in your browser and nothing is sent to a server. Your selected cities are stored only in your browser's local storage and restored on your next visit.
Can I check the time difference for a specific future or past date?
Yes. Turn off "Live update" and change the base date/time to see each city's local time at that exact moment — handy for testing candidate meeting times.
What do the "Prev day" / "Next day" badges mean?
Compared with the date in the base time zone, a city is tagged "Prev day" if its local date is one day behind and "Next day" if one day ahead — helping you avoid mistakes across the date line.
Does it work on smartphones?
Yes. It works on any device with a modern browser, including smartphones, tablets and PCs. No registration or installation required.
What do the colors in the meeting planner mean?
They indicate whether a given hour falls within working hours for each city. Green is typical working hours (9–18), yellow is early morning or evening (7–9 and 18–22), and grey is overnight (22–7). Pick a time where the green cells overlap to find a slot that works for participants in every city. The colors are a general guide only and may differ from someone's actual working hours.
What does the "DST" badge mean?
It indicates that the city is observing daylight saving time on the displayed date. DST periods vary by country and region, and offsets change around the switch-over dates. The tool detects this automatically via the browser's Intl API, but for important plans it is wise to confirm with a local official source.

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Related Guides

Time Zone and Time Difference Basics: UTC, JST, and DST Explained A clear guide to time zones and time differences: the difference between UTC and JST, how daylight saving time (DST) works, tips for scheduling meetings across countries, and how it all relates to Unix time.