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👩🏫 Classroom NEW
Online Timer / Countdown
Countdown timer for classrooms, presentations, pomodoro — fullscreen, color-changing warnings, alarm beep. Works offline.
All tools Browser-only
Quick:
05:00
Features
- 6 quick presets: 1, 3, 5, 10, 15 min, and 45 min (one class period)
- Color shifts: blue → amber (last min) → red (last 30s) → flashing red (over)
- Fullscreen mode for projecting to a class
- 3-beep alarm when time's up
- Tab title shows time so you can switch tabs and still see it
- Press Space to start/pause
Who this is for
K-12 teachers, tutors, TAs — classroom organization tools: timers, attendance, group makers, grade averages.
FAQ
Is student roster data safe?
Stored in browser localStorage — no server, no account. Incognito or cache clear = lost. Export CSV regularly for backup.
Does it work offline?
Yes. After the first page load, you can disconnect and the tool keeps working — perfect for classrooms with weak WiFi.
Related tools
See all tools →NEW
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Random Picker
Pick a random student from a list. No-repeat mode.
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Group Maker
Split a class into N balanced groups, or by group size.
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Pomodoro Timer
25/5/15, auto-advance, sound + notification, daily pomodoro count.
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Stopwatch
Stopwatch with 10ms precision, lap recording, Space/L/R shortcuts. Great for classroom, sports.
