Countdown & Pomodoro timers, stopwatch with laps, participant organizer, and timetable/planner tools for teachers and teams.
Users
48
−1 in 30 days
Rating
5.0 / 5
unchanged in 30 days
Ratings
2
0 in 30 days
Store rank
#109K
#91K among extensions
Version
2.10.0
updated 24 Jul 2026
Users
monthly, 10 months
Latest, 15 Oct 2026:48 usersMove the mouse over the chart for any month
Ratings count
monthly, 10 months
Latest, 15 Oct 2026:2 ratingsMove the mouse over the chart for any month
The Chrome Web Store rounds user counts down to the leading digit, so the user line moves in steps. The ratings count is exact and is the better signal of real adoption.
About TimerO - Timer, Picker & Planner
EXAM TIMER FOR EDUCATORS AND BEYOND
A powerful, classroom-optimized countdown timer built for teachers, invigilators, and test centers — with enough flexibility for anyone who needs a professional, distraction-free timer. The large, high-contrast display is designed to be read from the back of any classroom or projected onto a screen.
✨ KEY FEATURES
• Customizable title — click the title to rename it (e.g., "Year 11 Final Exam", "SAT Practice")
• Multiple subject cards — add separate countdown cards per subject, each with its own Subject, Grade, and Booklet Pages
• Edit cards on the fly — tap the ✏️ icon to update a card without stopping the timer
• Large labeled countdown — digits show HOURS · MIN · SEC at a glance from any seat
• Visual progress bar with smart color warnings:
— 🟢 Green: More than 20% time remaining
— 🟡 Yellow: 20% or less remaining
— 🔴 Red: Final 5 minutes
• Duration display — always shows the total exam duration alongside the timer
• Audio alarm when time expires
• Multilingual support — English, Arabic (RTL), French, and Spanish; exam rules auto-translate to the selected language
• Editable exam rules — customise the on-screen rules shown to students; saves per language
• 4 visual themes — choose the look that suits your display
• Upload your school logo — replaces the default icon with your institution's branding
• Screen wake lock — prevents the display from sleeping during an exam
• Fullscreen mode — one click for maximum visibility
• Works completely offline — no internet connection ever required
• No data collection — 100% private, all settings stored locally on your device
💡 PERFECT FOR
• Classroom exams and quizzes
• Standardised and competitive testing
• Study sessions and homework timers
• Workshops, seminars, and presentations
• Time-boxed group activities
• Any timed activity in a classroom or hall
📽️ PROJECTOR-OPTIMISED
Designed to be visible from every seat:
• Extra-large high-contrast countdown digits
• Clear HOURS / MIN / SEC labels
• Bold progress bar that changes colour as time runs out
• Optimised for 1280×800 and above (projectors and monitors)
📊 HOW TO USE
Click the extension icon → Open Timer
Enter Subject, Grade, and Booklet Pages (all optional)
Click Add Subject / Grade to create a card
Set the duration using the Hours / Minutes / Seconds picker
Click × to close the setup panel
Click START — the timer runs!
Need to edit a card while the timer runs? Tap ✏️ on any card, make changes, then click Update Card. The clock never stops.
🔒 PRIVACY FIRST
• No data collection or tracking
• No analytics, no ads — ever
• No account required
• No internet needed
• Everything stored locally on your device
Created by educators who know that a simple, reliable, visible timer is all you need.