How to Run a Timed Exam or Quiz Online (For Teachers and HR)

A practical guide to using a browser countdown timer to proctor timed exams — including fullscreen mode, sound alerts, Chromebook compatibility, and offline use.

A browser countdown timer is one of the most practical tools for proctoring a timed exam — and most teachers don't realize their computer already has everything they need. No app purchase, no school IT request, no account setup. This guide walks through exactly how to run a timed exam using a free online timer, covering setup, display, common questions, and what to do when things go wrong.

Setting up the timer before the exam

Open timerrapp.com/timer in your browser. Use the Hours, Minutes, and Seconds inputs to set the exact exam duration. For a 45-minute exam, set 0 hours, 45 minutes, 0 seconds. For a 90-minute exam, set 1 hour, 30 minutes, 0 seconds. Set the sound to whatever the class environment requires — Chime or Bells are softer choices if students are in the same room; Alarm or Beep carry further if the room is large.

Do not press Start until students have their materials ready and you're ready to begin. Starting early and resetting wastes time and creates confusion.

Going fullscreen for a smartboard or projector

Once the timer is set and you're ready to begin, press F11 on Windows or Ctrl+Command+F on Mac to enter fullscreen mode. The browser chrome disappears and the timer fills the entire screen. This is what you display on the projector or smartboard — students can see the countdown from anywhere in the room without straining.

Press Start to begin the countdown. The timer shows hours, minutes, and seconds counting down. In the final ten seconds, the display shifts to red automatically, providing a visual alert that time is almost up. When it reaches zero, the sound you chose plays.

To exit fullscreen at any time, press Escape or F11 again.

Will it work on a Chromebook?

Yes. The timer runs entirely in the browser using standard JavaScript and Web Audio — no plugins or extensions required. It works on Chrome, Firefox, Safari, and Edge on any device, including Chromebooks and iPads. The fullscreen shortcut on a Chromebook is the Fullscreen key (or F4 on some models).

What if the internet goes out during the exam?

Once the timer page has loaded, it runs entirely on your device — it does not require an active internet connection to count down. If your connection drops mid-exam, the timer continues without interruption. The only thing that requires internet is the initial page load.

Can students see it on a projector?

The timer is designed to be readable at a distance. The countdown display is large-format by default, and in fullscreen mode it scales to fill whatever screen it's on. For very large classrooms or lecture halls, the font size at fullscreen will be limited by the projector's native resolution rather than the software — a 1080p projector in a standard classroom displays clearly at 15 to 20 meters.

Setting a timer to a specific duration via URL

Some teachers want to be able to share a pre-configured timer with students for at-home practice. Rather than asking students to manually set a duration, you can link directly to a timer page for common exam lengths:

Each link opens a pre-set timer ready to start. Students click Start when they begin and Stop when they're done — no configuration needed.

For HR teams and assessment centers

The same approach works for in-person skills assessments, timed aptitude tests, or group exercises during hiring processes. Display the timer on a shared screen, go fullscreen, and press Start when the assessment begins. The sound alert at the end means you don't need to watch the timer yourself — you can circulate and observe participants while the timer handles the time boundary.

Try the free online timer →