Time Zone Converter

Time zones keep civil clocks broadly aligned with daylight around the world. Coordinated Universal Time (UTC) is the shared reference from which every local offset is measured: a location at UTC plus nine is nine clock hours ahead of UTC, and one at UTC minus five is five hours behind. Converting between two places is therefore a two-step calculation — take the source wall-clock time back to UTC, then apply the destination offset. The hard part is that offsets are not constant. Dozens of regions observe daylight saving time (DST), moving their clocks forward in spring and back in autumn on dates that differ by country and sometimes by year. New York is UTC-05:00 in January but UTC-04:00 in July; London swings between UTC+00:00 and UTC+01:00; most of Asia never shifts at all. This converter uses the full IANA time zone database built into your browser, so every conversion is computed for the exact instant you enter — the correct standard or daylight offset is applied automatically, including on the transition days themselves. Because meetings rarely involve just two places, you can add any number of destination zones and read them side by side, with a +1 or -1 badge whenever a zone lands on a different calendar date. The timeline view goes one step further: it lays a full 24-hour day of every selected zone on one grid, colour-coded into working hours, evening, and night, so overlapping windows for a call across three or more regions stand out at a glance. Click any hour to pin that moment across all zones, and step the date forward or back to see how DST changes the alignment from one week to the next. All calculations run entirely in your browser using the same zone rules your operating system relies on, so results stay correct even as governments revise DST legislation over the years. Your source and destination selections are stored locally in your browser, so the tool reopens exactly as you left it.