Two modes. Countdown takes hours, minutes and seconds — or one tap on a preset — and counts to zero. Alarm takes a clock time and rings at the next occurrence of it, today or tomorrow. Either way it finishes with a sound you choose from four, all generated in your browser: nothing is downloaded, so it rings offline as well. Pause, resume and reset at any time; your mode, fields and sound are remembered on this device.
| Data acquired | None. |
|---|---|
| Libraries used | Lit 3 — bundled into the tool file itself. |
| Data stored | Browser localStorage only, key uuutil.timer.v1 — your mode, the hours/minutes/seconds or clock time you typed, and the finish sound you picked. A running timer is not stored: closing the page ends it. |
| Data transmitted | None. |