What a full black screen is good for
Night clock
Turn on the clock for a minimal, dim bedside or desk clock that keeps the screen awake but barely lights the room.
OLED “off” look
On an OLED phone, TV or monitor a black screen switches the pixels off, so the display looks off while it stays awake.
Blank backdrop
Use a black screen behind a presentation, video recording or stream, or simply to hide what is on your display.
Screen checks
Pure black shows stuck pixels, dust, smudges and light leaking at the edges of LCD screens.
How to open a full black screen with the time
- Tick Show clock if you want the time on screen; leave it off for a plain black screen.
- Press Open Black Screen. The page goes fullscreen and the controls fade out after a couple of seconds.
- Adjust on the fly. Press C to toggle the clock, or ← → to switch to another color. Move the mouse or long-press to show the controls.
- Exit with Esc or the Exit button.
Tip: the clock moves a little every minute so it never sits on the same pixels, which protects OLED screens during long sessions.
Black screen on OLED vs. LCD
On an OLED screen every black pixel is switched off, so a full black screen looks completely dark and uses very little power. On an LCD screen the backlight keeps shining behind black pixels, so black looks dark gray and you may see light leaking at the edges or corners. If that glow looks uneven, check it with the backlight bleed test. Looking for a bright screen instead? Use the white screen.
Frequently asked questions
How do I make my screen completely black?
Press Open Black Screen. The page switches to your browser's fullscreen mode and fills the whole display with pure black. The controls fade away after a couple of seconds, and Esc or the Exit button takes you back.
How do I show a black screen with the time?
Tick Show clock before you open the black screen, or press C while it is open. A large, dim clock appears in the middle and updates every minute. You can switch it off again with the Clock button.
Does a black screen save battery?
On OLED screens, yes: black pixels are switched off, so a black screen uses very little power. On LCD screens the backlight stays on behind black pixels, so the saving is small.
Can a black screen with a clock cause burn-in?
The risk is low. The clock is dim and moves slightly every minute so it never stays on exactly the same pixels, which helps protect OLED screens. For very long sessions on an OLED, lower your screen brightness as well.
Why does my black screen look gray or glowing?
LCD screens have a backlight that stays on behind black pixels, so black looks dark gray, and light can leak at the edges or corners. That is backlight bleed or IPS glow. OLED screens switch their pixels off, so their black looks truly black.
Can I keep the black screen open all night?
Yes. In browsers that support the Screen Wake Lock API, such as Chrome, Edge and Safari, the page keeps your screen awake while it is open. Keep a laptop or phone plugged in, and use the clock option if you want a minimal night clock.