# Time Zone Converter

> Free time zone converter: enter a date and time in one of 40 world cities and see the matching time in another, with automatic daylight saving handling.

Enter a date and time in one city and instantly see what time it is in another, across 40 cities worldwide. Daylight saving is handled automatically for the exact date you pick.

*Interactive tool: enter your values at https://toollantern.win/time-zone-converter/ and results update instantly in your browser.*

## What this tool does

The converter takes a wall-clock time in a source city (say, 3:00 PM on March 10 in New York) and shows the simultaneous moment in a destination city (9:00 PM in Paris on the same date), with both cities' UTC offsets displayed.

## How the conversion works

Your browser ships with the IANA time zone database, the same data operating systems use for clock changes. The tool reads your input as a wall time in the source zone, resolves it to an exact UTC instant (correcting for that zone's offset at that moment), then formats that instant in the destination zone with **Intl.DateTimeFormat**. Offsets come from the same database, so they are correct for the date you picked.

## Worked example

**2026-06-15 15:00** in **New York** (UTC-4, daylight time) is **2026-06-15 21:00** in **Paris** (UTC+2, daylight time). In January the same 3:00 PM New York time (UTC-5, standard time) becomes 9:00 PM in Paris (UTC+1): the six-hour gap stays, but both offsets shifted.

## Daylight saving, handled

Because offsets are looked up per date, spring-forward and fall-back transitions are applied automatically. A meeting scheduled across a DST boundary converts correctly without you doing any math.

## Limitations

The list covers 40 major cities; smaller zones that share an offset with a listed city convert identically. Very old or far-future dates rely on current IANA rules, and governments do occasionally change them, so treat distant dates as approximate.

## Frequently asked questions
### How do I convert a time between two cities?

Enter the date and time, choose the source city and the destination city. The converted time appears instantly, with each city's UTC offset for that date.

### Does it handle daylight saving time?

Yes, automatically. Offsets are computed for the exact date you enter using your browser's IANA time zone database, so DST is applied exactly when it is in force in each city.

### Which cities are included?

40 cities across North and South America, Europe, Africa, Asia and Oceania, from Los Angeles to Sydney. Zones are stored by their IANA names (for example America/New_York).

### What if my city is not listed?

Pick any city that shares your time zone: cities on the same offset convert identically. For example, any US Eastern city works for New York, and most of Western Europe works for Paris.

### Why did the offset change between two dates?

One of the cities entered or left daylight saving between those dates. The converter shows the correct offset for each date, which is exactly why per-date conversion beats memorizing a fixed hour difference.

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Interactive version: https://toollantern.win/time-zone-converter/