This free white screen turns your whole display into a single colour. Use it to spot smudges when cleaning, hunt for dead or stuck pixels, check for backlight bleed, or add a little light to a video call.
- How to use the white screen
- What a white screen is useful for
- Cleaning your display
- Testing for dead and stuck pixels
- Black screen and backlight bleed
- Tips for a good test
- FAQ
- Related tools
How to use the white screen
- Choose a colour swatch: white, black, red, green, blue, yellow or gray. Use the custom picker if you need an exact shade.
- Press the full screen button. The page fills your display with the colour you picked.
- Click anywhere, or press the Space bar, to move to the next colour.
- Press Esc when you are finished to leave full screen and return to the tool.
- For a pixel check, start the dead pixel test. It cycles through the colours by itself every 2 seconds, so you can sit back and look at the whole panel.
The tool is a single web page, so there is nothing to install. It works on a laptop, a desktop monitor, a tablet or a phone, and it works the same way on Windows, macOS, Linux, Android and iOS because the browser does the drawing.
What a white screen is useful for
A pure white background shows every smudge, fingerprint and speck of dust. Switch the display off or keep it on for the check, then wipe and look again.
A flat colour makes faulty pixels stand out. Cycle through colours and look for dots that do not change.
A bright white screen next to your camera can soften shadows on your face. It is a stopgap, not a substitute for a proper light.
On a black screen in a dark room, pale patches near the edges point to backlight bleed on LCD panels.
Full screen gray and white show uneven brightness, tints or banding across the display.
Show a clean white or black field to check focus, keystone and brightness on a projector.
Using a white screen to clean your display
Dust and finger marks are hard to see on a busy desktop. A full white screen reveals them immediately. Work in good light, tilt your head so the light skims the glass and note where the marks are.
Turn the screen off before you wipe it, then use a dry or very slightly damp microfibre cloth. Never spray liquid straight onto the display, and avoid paper towels or strong cleaners, because they can scratch or strip coatings. Check your manufacturer's advice if you are unsure. When you finish, bring back the white screen and look for streaks, then repeat with a clean part of the cloth.
How to test for dead and stuck pixels
A pixel is made of three tiny subpixels: red, green and blue. When one fails, you see a dot that does not behave. There are a few types, and the colours help you tell them apart.
| What you see | Likely cause | Best colour to spot it |
|---|---|---|
| A black dot that stays black | Dead pixel, all subpixels off | White |
| A bright dot that stays one colour | Stuck pixel, one or more subpixels always on | Black |
| A white dot on a dark screen | Stuck pixel, all subpixels on | Black |
| A coloured dot on certain shades | A single faulty subpixel | Red, green and blue in turn |
Start the dead pixel test and watch the full cycle. Look at the whole screen, then move closer and scan the corners. Because each colour stays for 2 seconds, you have time to check each one without pressing anything. If you spot something, note the colour on screen when it appears and look again on the next cycle. Cleaning the screen first matters, as a speck of dust can look just like a dead pixel.
Warranty rules differ between brands, and many only accept a replacement above a certain number of faulty pixels. Take a photo, note the colour where the fault shows and read your warranty before you contact the seller.
Black screen, backlight bleed and glow
The same tool doubles as a black screen. Pick black, go full screen and turn the room lights down. On an LCD, the picture should look evenly dark. Bright clouds in the corners or along an edge are backlight bleed. A small amount is normal on many monitors, and it is more visible at high brightness, so lower the brightness before you judge.
Glow is a softer haze that changes as you move your head, and it is common on IPS panels. On an OLED screen black should look truly black because each pixel switches off. If an OLED shows a grey haze, check the brightness and any power saving setting first.
Tips for a good test
Set the screen to your normal brightness, then try one pass at full brightness. Let the display warm up for a few minutes. Turn off night light and colour filters, because they tint the colours you see. Remove any screen protector film that is peeling, since it can look like a fault.
Avoid leaving a bright static colour up for hours. Modern screens cope with short tests, but there is no reason to run one for long, and OLED panels in particular can show image retention after very long static images. If you only need a few minutes of light or a quick inspection, that is more than enough.
Frequently asked questions
How do I make my screen fully white?
Open the tool, choose the white swatch and press the full screen button. The whole display turns white until you click or press Space for the next colour. Press Esc to leave. Use the custom picker if you want a warm or cool white instead.
How do I find a dead pixel?
Start the dead pixel test and watch the colours change every 2 seconds. A dead pixel stays black on white, while a stuck pixel stays one bright colour on black. Clean the screen first, because dust can look like a faulty pixel.
Can I use a white screen as a light?
It gives a soft glow and can reduce shadows on your face during a video call, so it works in a pinch. It is much weaker than a real lamp, so keep brightness high and do not expect it to light a whole room.
How do I exit full screen?
Press the Esc key. This leaves full screen and returns you to the tool page. Clicking or pressing Space does not exit, it only moves to the next colour. If the page ever seems stuck, reload it and start again from the swatch list. Nothing changes on your device, and no settings are saved.
Does it have a black screen too?
Yes. Black is one of the swatches, so you can use the same tool for a black screen. It is useful for checking backlight bleed in a dark room, resting your eyes, or showing a blank field on a projector.
Does the tool install anything or collect data?
No. It is a normal web page that draws colours in your browser. There is nothing to download, and it does not need your camera, microphone or files. Close the tab when you are done and the test is over.
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