How this timer works
Enter a duration and the timer counts down to zero, then sounds an alarm and announces the timer by name. You can run as many timers at once as you like — each keeps its own name, duration and progress — which is what makes this useful for cooking, where three things finish at three different times, or for a workout circuit with different intervals per station.
It does not drift in a background tab
Most browser timers lose time when you switch tabs, because browsers throttle background JavaScript to save battery. A timer that counts down by subtracting a fixed amount on every frame will quietly fall behind, sometimes by minutes over a long duration. This one records the moment it should finish and compares against the real clock on every tick, so switching tabs, locking your phone, or leaving it running for an hour does not change when the alarm fires.
Looping and repeat counts
Set a loop count and the timer restarts itself when it reaches zero. Three loops of five minutes gives you fifteen minutes broken into thirds with an audible marker at each boundary. Set it to endless for something like a stretching routine, where you want a nudge every few minutes until you decide to stop.
Keeping the screen awake
On phones and tablets the screen will normally sleep partway through a long timer. Where the browser supports it, this page asks the system to keep the display on while a timer is running, and releases that request the moment the last timer stops.