Time Zone Converter
Convert a date and time between any two places, with summer time handled automatically and the day shown, so you know if it lands tomorrow or yesterday.
About this tool
Pick the date, the time and the two places, and the converted time appears with the day of the week, so you can see straight away if a call falls on the next day. It uses named time zones (Europe/London, America/New_York and every other zone your browser knows), so summer time is applied automatically for the date you choose. That matters because the UK, Europe and North America change their clocks on different weekends, and for a few weeks each spring and autumn the usual gap between London and New York is four hours instead of five.
The line under the result shows how far ahead or behind the other place is, and each zone's UTC offset on that date. If you pick a time that's skipped or repeated when the clocks change, the tool says so. Your own time zone is at the top of each list, and Use the time now fills in the current date and time.