Time Zone Converter

Time zones are one of those things that sounds simple — the Earth rotates, the sun reaches its highest point at a different moment in different longitudes, so local noon is offset from Greenwich Mean Time — until you actually need to schedule something across them, at which point daylight saving time, half-hour offsets, date-line wrapping, and the fact that not every country observes DST on the same Sunday all combine to make a manual calculation surprisingly error-prone. The standard rule of thumb — add or subtract the offset — works only if you happen to know the correct offset for both locations on that specific date, which itself changes twice a year in most of Europe and North America, sometimes on different weekends. This converter handles that for you. You pick two IANA time zones (e.g., 'Europe/London' and 'America/Los_Angeles'), enter a date and time in the source zone, and the tool tells you what the clock reads at that same moment in the target zone, using your browser's built-in Intl.DateTimeFormat engine — the same engine that powers the date and time display in every modern operating system — to look up the correct UTC offset for each zone on the entered date, including whether daylight saving is in effect. This means the result reflects the real-world, date-specific offset, not a fixed annual average. The time zone list is drawn from the IANA Time Zone Database (also called tzdata or the Olson database), the same canonical list used by Linux servers, cloud platforms, smartphones and every major programming language's standard library. The list shown in the dropdown includes the most commonly searched cities and regions grouped by continent, with the IANA identifier (e.g., 'America/Chicago') alongside a human-readable label that includes the city name and standard time abbreviation. You can also type to filter the list — typing 'london' will narrow the options to Europe/London and any other zone with 'London' in the label — to avoid scrolling through the full list. All of this runs entirely in your browser. The converter uses the Intl API built into the browser's JavaScript engine — no server request, no API call to an external time zone service, no data leaving your device. The time zone database used for the offset lookup is the one bundled with your browser, which typically updates through normal browser updates every few months to reflect the latest DST rule changes (which countries do occasionally change, sometimes on short notice).