An alarm for a time, not a countdown

Choose a time of day and this tab will ring at it. An alarm is different from a timer in one way that matters: it fires when the clock says so, even if the clock moved.

An alarm follows the clock; a timer follows real time

Set an alarm for 7am the night the clocks go forward and it fires at 7am, an hour of real time earlier than you might expect. Set a seven-hour timer and it runs seven real hours. Both behaviours are correct and neither is a substitute for the other, which is why this site has both.

A closed tab cannot ring

Nothing running in a web page survives its tab being closed. An alarm that reaches you regardless is scheduled on a server and delivered by email or push, and that is the one capability here that needs an account — not because ringing is expensive, but because a scheduler slot is a real thing somebody has to run.

Questions

Will an alarm go off if I close the tab?

Not on its own — a closed tab runs no code, and any site claiming otherwise is relying on a notification permission you granted earlier. An alert that reaches you with everything closed is scheduled on our servers, and that is the one thing here a membership pays for.

Does a timer survive a daylight-saving change?

Yes, and the distinction matters. A countdown measures elapsed real time, so a timer set for six hours across a spring-forward still runs six real hours even though the wall clock advances seven. An alarm set for a wall-clock time does the opposite: it fires when the clock says so, which is what you want from an alarm.