For long sits that need structure: a quiet bell strike every few minutes marks the passing time without asking you to open your eyes.
In a twenty- or thirty-minute sit, time goes strangely — five minutes can feel like an hour, and an hour like five. A soft interval bell every few minutes does two jobs: it proves time is actually passing, and it gives wandering attention a no-blame place to return to. Teachers of body-scanning and breath-counting styles have used interval bells for exactly this since long before browser timers.
Set the interval above (off, 1, 3, 5, or 10 minutes), choose the same bell family as your start and end sound, and press Begin. Interval strikes are played quieter than the opening and closing strikes, so the sit keeps a shape: one clear bell to start, quiet marks along the way, a final strike to finish.
Body scan: 20 or 30 minutes with a bell every 10. Breath counting: 15 minutes with a bell every 5. A slow 60-minute sit: accept a mark at ten and twenty past, or run two sessions back to back. There is no wrong configuration; the interval is a tool, not a rule.
Noticeably quieter — about half the gain — so it marks time without startling you. The opening and closing strikes are full volume.
The timer is anchored to the wall clock, not a counting loop, so interval marks stay accurate even in background tabs or after the screen dims. On laptops with a compatible browser, the screen is kept awake during the sit.
Ten minutes is the longest option on purpose: on longer sits, two or three quiet marks are usually enough, and the closing bell is what ends the sit.
No account, no sync, nothing leaves your device. Export a backup anytime — it also works as a way to move your history to another browser.