Timezone Converter
Pick a source and a target timezone, enter a date and time, and see the equivalent local time on the other side. Built on the browser's IANA timezone database via Intl APIs, so daylight saving transitions are handled correctly for every region. Also shows the matching UTC instant.
2026-08-21 01:08:00
UTC · GMT+0
2026-08-21 01:08:00
UTC · GMT+0
UTC: 2026-08-21T01:08:00.000Z
How to use
- Pick the source timezone — defaults to your local zone.
- Pick the destination timezone.
- Enter the date and time, or click Now.
- Read both sides and copy the result.
Frequently asked questions
- How is DST handled?
- The browser's IANA timezone data is used (via Intl.DateTimeFormat), so transitions like spring-forward and fall-back are accurate per region.
- Why do I see hundreds of timezones?
- IANA lists one zone per region that has had a unique offset history. If your country isn't visible, try its capital — e.g. Asia/Seoul, Europe/London.
- What about UTC offsets like +09:00?
- Each card shows the offset (like GMT+9) right below the time. The bottom row shows the matching ISO 8601 UTC string.
- Is my data saved?
- Source and destination zones are kept in your browser's local storage so the form remembers your last choice — nothing is uploaded.
Guides on this topic
- Working with Time Zones and Unix Timestamps Without Bugs Why time is so hard to get right in software — UTC, Unix timestamps, time zones and DST — and a small set of rules that prevent the most common date-handling bugs.
- How Cron Schedules Actually Work The five cron fields and their syntax, the day-of-month/day-of-week rule almost everyone gets wrong, what daylight saving does to a nightly job, and how to design schedules that survive restarts.
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