Daylight Saving: Missing and Repeated Local Times
Handle a clock-change date without silently choosing the wrong instant.
A local clock label can be missing
When clocks move forward, some local times do not occur. In New York on March 8, 2026, the clock jumps from the 01:00 hour to the 03:00 hour. A request for 02:30 that day is invalid. A converter should explain the gap rather than quietly moving your appointment.
An autumn time can happen twice
On November 1, 2026, New York’s 01:30 occurs once before and once after the clock moves back. The two readings are an hour apart in elapsed time. Choose the earlier or later occurrence explicitly when converting an appointment in that repeated hour.
Offsets make the distinction visible
The earlier New York occurrence uses UTC−04:00 and the later one UTC−05:00. Their UTC instants differ even though the local date and clock digits match. Keep the UTC instant or offset with an exported schedule when this distinction matters.
Rules belong to a place and a date
Not every city changes clocks, and countries can change their rules. Use a named time zone on the actual date rather than assuming today’s offset applies all year. The converter displays its bundled data version; future legal rule changes require a data update.
Put it into practice
Time Zone Converter
Convert a date and time between world time zones. See the destination date, UTC offset and daylight saving time for your chosen moment.
Time & planningWorld Meeting Planner
Compare the same meeting across three time zones, with local dates and a working-hours indicator for every participant.
Time & planningUnix Timestamp Converter
Convert Unix timestamps in seconds or milliseconds to UTC dates, or turn an ISO 8601 date and time into a timestamp.
Numbers & text