Raspberry Pi Countdown Timer Display for Events, Step by Step
A dedicated stage timer can cost hundreds. A Raspberry Pi and a spare monitor can do the same job for about forty euros — boot straight into a full-screen countdown you control from your phone. Here is the exact setup.
Quick Summary
- Flash Raspberry Pi OS and enable auto-login to the desktop
- Launch Chromium in kiosk mode pointed at your TimedFlow viewer link
- Add an autostart entry so the timer appears on every boot
- Control the countdown remotely from a phone or laptop
Why a Raspberry Pi Beats Dedicated Timer Hardware
Purpose-built stage timers are excellent, but they are expensive, single-purpose, and often tied to proprietary controllers. A Raspberry Pi countdown timer gives you the same result — a big, bright, full-screen clock on any HDMI display — using hardware you may already own. Because the timer itself is a web page served by TimedFlow, the Pi does nothing but display a URL. That keeps the device dead simple: no software to maintain, no firmware to update, and if the Pi ever dies you swap in another for the cost of a nice dinner.
Roughly €40 of Hardware
A Pi, a microSD card, and a power supply drive any monitor or TV you already have. No per-display license.
Set and Forget
Once configured, the Pi boots straight into the timer. Plug it in at the venue and it just works.
Step 1: Create the Timer Link
Before touching the Pi, create the room the display will show. On any computer, open timedflow.com/r/new — no account needed. You land on the controller; note the viewer URL in the form timedflow.com/r/<slug>. That is the address the Pi will open. Keep the controller URL (/r/<slug>/controller) on your phone to run the clock during the event.
Step 2: Flash and Prepare the Pi
Use Raspberry Pi Imager to flash Raspberry Pi OS (with desktop) to a microSD card. In the Imager settings, set your Wi-Fi credentials and enable SSH so you can configure the Pi headlessly. Boot it, then in raspi-config → System Options → Boot / Auto Login choose Desktop Autologin so no keyboard is needed at the venue.
Step 3: Launch Chromium in Kiosk Mode
Kiosk mode fills the entire screen with the page — no address bar, tabs, or cursor clutter. Test it from a terminal first, replacing the URL with your viewer link:
chromium-browser \ --kiosk \ --incognito \ --noerrdialogs \ --disable-infobars \ https://www.timedflow.com/r/YOUR-SLUG
On Raspberry Pi OS Bookworm the binary may be chromium instead of chromium-browser. The countdown should now fill the display. Press Alt+F4 or Ctrl+C in the terminal to exit while testing.
Step 4: Autostart on Every Boot
To make the timer appear automatically, add a desktop autostart entry. Create the file ~/.config/autostart/timer.desktop with:
[Desktop Entry] Type=Application Name=TimedFlow Timer Exec=chromium-browser --kiosk --incognito --noerrdialogs --disable-infobars https://www.timedflow.com/r/YOUR-SLUG
Reboot with sudo reboot. The Pi should power up, log in automatically, and open your countdown full-screen with no interaction. It is a good idea to also disable screen blanking (in raspi-config under Display Options) so the timer never goes dark mid-event.
Step 5: Control the Timer From Your Phone
One Display, Remote Control
The Pi only ever shows the viewer. All the buttons live on the controller link you kept on your phone. Start, pause, add a minute, send a flash message, or reset — the Pi display updates instantly over the network. You never need a keyboard or mouse plugged into the Pi at the venue.
- Run one Pi per room and control them all from a single phone
- Wrap-up colors turn the whole screen amber then red as time runs out
- Swap in a backup Pi in seconds if hardware fails — same URL, same room
Great For Any In-Room Display
This kiosk setup powers a confidence monitor for a stage timer, a countdown at a conference breakout room, or a wall clock for a hybrid event. Prefer casting to a TV instead of wiring a Pi? Read how to show a timer on any TV. See everything the timer can do on the features page.
Build Your Own Stage Timer This Weekend
Create a free timer room, point a Raspberry Pi at the viewer link, and control the countdown from your phone. No account, no dedicated hardware.