How do I run Chrome in kiosk mode?

Launch it from the command line with the kiosk switch followed by the page address, for example chrome --kiosk https://example.com. The browser opens fullscreen with no address bar or tabs. Add that command to the machine's startup items so it relaunches automatically after a reboot.

How do I stop a signage screen going to sleep?

Disable sleep, screen blanking and the screensaver in the operating system's power settings, and set the lid-close action to do nothing on a laptop. A page can also hold a screen wake lock, but system settings are more reliable because they survive a browser crash.

Will a clock burn into a display screen?

On OLED panels a permanently static image can leave a faint ghost over hundreds of hours. Ordinary LCD and LED-backlit monitors are not meaningfully affected, which makes them the safer choice for permanent signage. Lower brightness and light-on-dark layouts reduce the risk further.

How large should text be on a display screen?

A common signage rule of thumb is about one inch of character height for every ten feet of viewing distance. A screen read from thirty feet therefore wants digits around three inches tall. Contrast and a plain, non-condensed typeface matter as much as raw size.

Kiosk Clock Display Setup

The screen in a reception area, a gym, a workshop or a waiting room is usually running something more complicated than it needs to. A kiosk clock display is the opposite: one page, no controls, nothing to click, showing the current time large enough to read from the far side of the room. It is the easiest signage there is to install and the easiest to forget about, which is exactly the point.

This article covers launching a browser in kiosk mode, stopping the screen sleeping, avoiding burn-in on a panel that never changes, sizing digits for the room, and making the whole thing survive months without anyone touching it. The fullscreen display mode is the page to point the machine at.

What Is A Kiosk Clock Display?

A kiosk clock display is a screen running a browser locked to a single clock page, with no address bar, no tabs and no way for a passer-by to navigate away. The machine boots, the browser launches, the clock appears, and nothing else is reachable.

The hardware behind a kiosk clock display barely matters. A small form-factor PC, a mini computer behind the panel, an old laptop with the lid open, a tablet on a stand: any of them will run a clock for years. What matters is that the software starts unattended and stays put. That is what separates a kiosk clock display from someone opening a browser and pressing F11, which lasts until the first restart.

How Do You Launch A Browser In Kiosk Mode?

Start the browser with the kiosk switch and the page URL. Chrome and Edge both accept a command line of the form chrome --kiosk https://example.com, which opens fullscreen with no interface and ignores most attempts to leave the page.

The details that make it stick:

Autostart: add the command to the machine's startup items, a scheduled task at logon, or a systemd user service on Linux, so a power cut is self-healing.
Auto-login: a kiosk that stops at a password prompt after a reboot is not unattended. Configure the operating system to log in automatically to a dedicated restricted account.
A clean profile: point the browser at its own profile directory so restore prompts, update notices and previous sessions never appear over the clock.
Disable notifications and updates prompts: anything that can draw a dialog over the display will eventually do so at the worst moment.

Purpose-built digital signage software adds remote management and scheduling, which is worth having across a fleet of screens. For one or two panels showing the time, a kiosk clock display built from kiosk mode plus autostart is less to go wrong.

Stopping The Screen From Sleeping

Turn off sleep, screen blanking and the screensaver at the operating system level rather than relying on the page. A kiosk clock display that has gone dark is indistinguishable from a broken screen, and nobody in a lobby will move the mouse to wake it.

Set the display timeout to never, disable the screensaver, and on a laptop set the lid-close action to do nothing if the lid will be shut. The Screen Wake Lock API is a useful second line of defence: a page can request a screen wake lock and the system will hold the display on while the page is visible. It is not a substitute for the system settings on a permanent installation, because the lock is released whenever the page is hidden, and a browser crash takes it with it. The trade-offs are set out in screen wake lock and battery.

Avoiding Burn-In On A Static Kiosk Clock Display

Assume burn-in will happen on OLED and plan around it. A clock is the worst case for a panel: the same digits in the same position, hour after hour, with the colon and the leading characters changing least of all.

The practical measures are cheap:

Choose LCD for permanent installs: ordinary LCD and LED-backlit panels are not meaningfully susceptible to burn-in, which makes them the safer choice for a screen that will show one thing forever.
Run light on dark: on OLED this lights far fewer pixels, cutting both wear and power draw.
Reduce brightness: a kiosk clock display rarely needs full brightness, and lower brightness slows panel wear directly.
Schedule an off period: switching the screen off overnight, or when the building is empty, removes a third of the running hours at no cost to anyone.

How Big Should The Digits Be?

Size the digits on a kiosk clock display for the furthest viewer, not the nearest. A long-standing signage rule of thumb is roughly one inch of character height for every ten feet of viewing distance, so a clock read from thirty feet away wants digits about three inches tall.

Legibility is not only size. Contrast decides how well the digits survive ambient light, and a screen opposite a window will wash out at times of day nobody tested. Keep the typeface plain, avoid condensed faces and thin weights, and use 24-hour format on a shared display so there is no AM or PM to misread from a distance. Showing seconds is a judgement call: they prove the display is alive rather than frozen, which is reassuring on an unattended screen, but they also add constant motion in a space where people are trying to concentrate. In a waiting room, seconds help; in a library, they do not.

Unattended Reliability On A Kiosk Clock Display

Assume nobody will look at the kiosk screen for six months. That single assumption drives every remaining decision, from how the browser starts to how the time stays correct.

A clock display is unusually forgiving here, because the time is read from the local machine rather than fetched over the network. The display keeps working through an internet outage, a DNS failure or a server problem, provided the page was already loaded. What it cannot survive is a wrong system clock: an unattended screen has nobody to notice it slipping, so network time synchronisation matters more on signage than on a laptop. Leave the machine online and set to synchronise automatically, and it will stay within milliseconds of true time; take it offline for a month and ordinary quartz drift will move it by a minute or more, as explained in NTP vs browser time and browser clock accuracy. Also worth doing: give the machine a reliable power supply or a small UPS, and set the operating system to restart automatically after a power failure.

Conclusion

A kiosk clock display is a small amount of setup that then runs itself. Launch the browser with the kiosk switch pointed at a clean fullscreen clock, autostart it at logon, disable sleep and the screensaver at the system level, choose an LCD panel or run light digits on dark to limit burn-in, and size the numbers for the furthest person in the room. Keep the machine synchronised and it will show the right time for years without attention. Start with the fullscreen display mode or the plain live clock, and see the rest of the displays on livetime.now.

Kiosk Clock Display: Running A Clock On Lobby And Signage Screens