The current time in every city you care about, on one 24-hour grid. Your own zone first, day and night shaded, as many rows as you need. Free, no account.
Each row is a city and each column is the same instant, so the column under the marker is "right now" everywhere at once. The shading marks the working day, the evening and the night in every zone - the thing a world time clock is actually for, since 14:00 in Prague being 05:00 in San Francisco matters more as "they are asleep" than as a number. Add rows by city name, country, zone abbreviation or IANA id, reorder them, and the board is saved in your browser for the next visit.
The grid does more than tell the time: tapping an hour turns it into a time zone converter and meeting picker, with the slot exported to Google Calendar, Outlook or the clipboard. And if your day runs on the zero-offset clock itself, the Zulu time page shows the current UTC live and converts any Zulu time to local.
A world clock answers "what time is it there right now"; a converter answers "when is 3 PM their time in my time". This page is the same grid doing both: the highlighted column is the current moment in every row, and tapping any other hour converts it across all of them.
Type its name into the add box under the grid - city, country, zone abbreviation like PST, or an IANA id like Asia/Tokyo all work. Rows can be reordered and are saved in your browser, so your set of cities is still there next visit.
Yes. Every cell is computed from the IANA time zone database, so a city that is currently on summer time shows its actual clock, and on transition days the skipped or repeated hour appears right in the row.