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Productivity & Business Tools

Time Zone Converter

Convert time between different time zones

How to use

  1. Select source time zone
  2. Select target time zone
  3. Enter date and time
  4. View converted time and difference

Use cases

  • International meetings
  • Travel planning
  • Remote work coordination
  • Global events

About the Time Zone Converter

A time zone converter translates a wall-clock time in one zone to the equivalent moment in another zone, accounting for daylight saving time differences. Getting this right matters for scheduling international meetings — a naive implementation can silently mistime a meeting by an hour during DST transitions. This tool uses Intl.DateTimeFormat per-instant offset calculation, which is always correct.

Features

  • DST-aware offset computed at the input datetime, not 'now'
  • 13 common IANA zones (UTC, US, EU, APAC)
  • Difference in hours + ISO UTC instant displayed
  • Copy converted time in one click
  • Intl.DateTimeFormat under the hood — always correct

How it works

  1. Enter the date and time.
  2. Pick the source ('From') time zone.
  3. Pick the target ('To') time zone.
  4. Read the converted time, offset, and UTC instant.

Frequently asked questions

Why is this different from other converters?

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Many naive converters use Date.getTimezoneOffset(), which returns today's offset — not the offset at your target datetime. During DST transitions (spring forward/fall back), that's wrong by an hour.

What about the US DST switch in November?

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2:00 AM EDT on switch day is a valid time; 2:30 AM EDT crosses into EST. Our converter computes the offset at that exact moment, so the math is correct.

Can I add more zones?

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The IANA database has 400+ zones. We're surfacing the 13 most common in the UI and adding a 'custom zone' input in a future update.

Does it handle historical dates?

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Yes, as long as your browser's ICU data includes the historical rules (most do). Pre-1970 dates may be approximate.

Is the time saved anywhere?

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No — conversion runs entirely in your browser.