Classroom Timer
This classroom timer shows time on digits the whole room can read from the board, with sound off by default — when time is up the screen flashes fern green instead of buzzing, so a silent classroom stays silent. Around 40,500 US searches a month ask for a classroom timer (Semrush, 2026), and teachers keep rebuilding their own ad-free versions because the big names in this niche are either ad-heavy or blocked on school networks. This one is a single self-contained page: no ads, no sign-up, no login wall, and it keeps working offline once loaded.
Done at —
We keep the tab title updated too, so you can watch it from another tab.
Sound level is remembered on this device. Muted? Time-up flashes the screen instead.
Board-readable
White digits on a fern disc, readable from the back row.
Silent time-up
The screen flashes green: no buzzer, no scramble for the volume.
No network needed
One self-contained page; it keeps working if school Wi-Fi drops.