Black Screen — Fullscreen Black Display for OLED, Dark Rooms & Testing

A pure black fullscreen screen, one click away. Great for dark rooms, OLED displays and spotting bright dead pixels or backlight bleed. Free and local.

What it does

This page fills your display with pure black (#000000) and goes fullscreen on request. It’s handy when you want a dark screen without turning the device off: in a dark room, as a background for a monitor you’re about to photograph, to check a display for bright stuck pixels, or to look for backlight bleed along the edges.

How it works

On an OLED or similar self-lit panel, black pixels are switched off, so a black screen uses little power and gives true black. On a typical LCD, the backlight stays on behind the panel, so black looks dark grey and light can leak at the corners; that leakage is exactly what a black test screen helps you see. A small clock overlay (tick Show a clock) shows the time without lighting the whole screen. The overlay picks a readable text color automatically.

How to use it

1. Dim the room, then press Go fullscreen.
2. Look at the edges and corners for light leaking through, and across the panel for bright specks.
3. Turn on the clock if you want a dim bedside time display, then lower the Dimmer if the numbers are too bright.
4. Press Esc to exit.

FAQ

Does a black screen save power?

On OLED displays, yes, noticeably. On LCDs the backlight keeps running, so savings are small.

How do I find a stuck bright pixel with this?

Go fullscreen in a dark room and scan the screen. A pixel stuck on white, red, green or blue stands out against black. The Display test mode in the Color Screen tool will also show you stuck-dark pixels on the other colors.

Will my screen still turn off after a while?

Yes, unless you tick Keep the screen awake. If you only need the screen to stay on, the Stay Awake tool does that without a color.

Privacy

Everything runs in your browser. Nothing is uploaded and no network requests are made while you use it.