Full Screen Timer
The short answer: this is a free on-screen countdown — pick a duration, press Start, then press Fullscreen to fill the screen so a whole room can read it. For a timer that floats on top of your slides and windows (not just a fullscreen browser tab), download SlideTimerApp, the free Windows overlay.
A full screen timer does one job well: it puts a big, unmissable countdown on screen so everyone in the room reads the same clock. Use the controls above to set a duration, then press the Fullscreen button to display the timer on screen edge to edge. There's nothing to download to use it in the browser, nothing to sign up for, and the same page works for a quick 1-minute drill or a 30-minute exam.
How to make a timer full screen
Going full screen takes three steps in any modern browser — no install, no settings to dig through.
- Set the time. Tap a preset (1, 5, 10, 15 or 30 minutes) or type your own minutes, then press Start.
- Press Fullscreen. The big digits expand to fill the whole screen, so the countdown is readable from the back of the room or across a meeting table.
- Press Esc to exit. Hit the Esc key (or the Fullscreen button again) to drop back to the normal page whenever you like.
The Fullscreen button uses your browser's own full-screen mode, so the countdown takes over the entire display — no menu bars, tabs or address bar in the way. That's what makes it an easy way to display a timer on screen for a group: nobody has to squint at a small window, and the digits stay legible from the far side of a hall or classroom.
When a full-screen timer helps
An on-screen countdown earns its place anywhere a group needs to share the same clock:
- Classrooms. Project the timer so the whole class can see how long is left on a task — it quietly ends the "how much longer?" questions. See the classroom timer page for more ideas.
- Events. Keep speakers, panels and lightning talks to time with a countdown the audience can also read.
- Meetings. Time-box stand-ups, retros and brainstorms so discussions stay focused and finish on schedule.
- Exams. Display the remaining time at the front of the room so every student works to the same clock.
Full-screen browser timer vs an always-on-top overlay
Filling the screen with one tab is great for a shared display. But the moment you start presenting, a browser tab can't sit on top of your slides — that's where the desktop overlay comes in. A full-screen browser timer needs the whole screen to itself, so when PowerPoint takes over in Slide Show mode the countdown disappears behind it. An always-on-top overlay solves that: it floats a small, transparent timer above whatever you're showing, so it stays visible while your slides run underneath.
| What you need | This full-screen web timer | SlideTimerApp overlay |
|---|---|---|
| Fills the screen | Yes | Yes |
| Floats over your slides while you present | No (browser tab) | Yes |
| Works in PowerPoint Slide Show | No | Yes |
| Needs the browser open | Yes | No (portable app) |
Want it on top of your slides, not just fullscreen?
SlideTimerApp floats a transparent, always-on-top countdown over PowerPoint, Google Slides or Canva — free for Windows, and it stays visible while you present.
Download SlideTimerApp free ~3 MB · Windows · works offlineMore timers
Online timer with sound
A big countdown with an alarm at zero.
Classroom timer
A big, visible countdown for lessons.
Download SlideTimerApp
Float a countdown over your slides.
Frequently asked questions
How do I make a timer full screen?
Set your time and press Start, then press the Fullscreen button so the countdown fills the whole screen. To exit full screen, press Esc or the Fullscreen button again. It works in any modern browser and needs no install.
Is this full screen timer free?
Yes. The on-screen countdown is completely free, with no sign-up, no ads and no limits. You can use it as often as you like for classrooms, events, meetings and exams.
Can I show the timer on top of my slides instead of fullscreen?
A browser timer can fill the screen, but it can't float over a running PowerPoint Slide Show. Download SlideTimerApp, a free Windows overlay that keeps the countdown always on top of your slides and other windows while you present.
Does the full screen timer have an alarm?
Yes. The timer plays an alarm tone when the countdown reaches zero, and the digits turn red in the final seconds, so you get both an audible and a visual cue. Make sure your device isn't muted.