Dead Pixel Test

Fill your screen with solid colors and spot any pixel that stopped working — a faulty one shows up as a tiny dot that doesn't match. Takes about a minute.

Tip: wipe the screen first — a speck of dust is the most common false alarm.

How to Find Dead Pixels on Your Screen

Fill your screen with solid colors, one after another, and any faulty pixel will give itself away as a tiny dot that does not match. Takes about a minute — nothing to install.

How the test works

The test fills your whole screen with one solid color at a time. Against a single color, any pixel that does not join in stands out immediately as a tiny dot that stays the same wherever the picture changes. Step through every color, look closely — corner to corner — and note any dot that appears on some colors but not others.

Dead pixel or stuck pixel?

A dead pixel gets no power and stays dark — you will see it as a black dot on the white screen. A stuck pixel is frozen with one part switched on, so it shows as a tiny red, green or blue dot that is easiest to spot on the black screen. The difference matters: stuck pixels sometimes come back to life, dead ones almost never do.

Why these colors

Each color has a job. White exposes dead pixels as dark dots. Black exposes stuck pixels as bright ones. Pure red, green and blue light up one part of every pixel at a time, so a dot that only appears on one of them tells you exactly which part has failed. The gradient screen at the end catches pixels that work but shine brighter or darker than their neighbors.

The gradient screen

The last screen shows smooth color ramps from black to white, red, green and blue. On a healthy display each ramp looks perfectly even. If you see distinct stripes instead of a smooth blend, your display or its settings are compressing colors. It is also one more chance to catch defective dots against changing backgrounds.

Can it be fixed?

A stuck pixel is occasionally revived by gently massaging the spot through a soft cloth while the screen shows a changing picture, or just by leaving the display on for a while — some recover on their own within days. Be gentle: pressing hard can damage more pixels than it fixes. A dead pixel is a hardware fault and no rubbing will bring it back.

Warranty and returns

Manufacturers usually tolerate a few defective pixels before a display qualifies for replacement, and the rules differ between brands and even between cheaper and premium models of the same brand. If you find pixels on a new device, count them, photograph them on contrasting colors, and check the maker's pixel policy — a fresh purchase can often simply be returned instead.

Just need a white screen?
A clean, bright, full-white page — handy as a light source and for spotting marks on the screen.
Open the white screen
Ghost images on your screen?
See whether shadows of old images stay on your screen — a quick check every OLED owner should run.
Check for burn-in

Frequently asked questions

Clean the screen first so dust cannot fool you, press "Start test", and the page will fill your display with solid colors. Click, tap or press any key to move to the next color, and look over the whole screen each time. A defective pixel shows as a tiny dot that stays in the same spot from picture to picture. Press Escape when you are done.
A dead pixel stays black on every color — easiest to see on the white screen. A stuck pixel glows in one color — usually red, green or blue — and is easiest to see on black. There are also pixels that are only brighter or darker than the rest — watch for those on the gradient screen at the end.
Sometimes, if it is stuck rather than dead. Leave the screen on for a few hours, or very gently massage the spot through a soft cloth while the test cycles colors. Many stuck pixels also recover on their own. If the dot is simply black on every color, it is dead — that is physical damage only a screen replacement fixes.
It depends on the manufacturer's pixel policy. Many allow two or three defective pixels on a monitor before the warranty applies, some premium lines promise zero. Bright stuck pixels in the middle of the screen are usually treated more strictly than dark ones near the edge. If the device is brand new, a straightforward return is often easier than a warranty claim.
Yes. The test is just a web page, so it runs on anything with a browser — phones, tablets, laptops and TVs. On a phone, add the browser's fullscreen or hide-toolbar option if available and tap to change colors. For a TV, open this page in the TV's browser, or plug in a laptop and mirror the picture.
Move to a different color and watch the dot. Dust sits on top of the glass — it looks slightly fuzzy, keeps its gray look on every color, and wipes away. A defective pixel is perfectly sharp, sits exactly in the pixel grid, and changes with the background: visible on some colors, gone on others. When in doubt, wipe the screen and run the cycle again.
Completely. The screen simply shows solid colors — the same thing it does when a movie fades to black. Staring at them cannot wear anything out. One practical note: your computer may dim or fall asleep on its own schedule while you look, so wiggle the mouse now and then or extend the sleep timer.
Yes. Everything happens right in your browser: no download, no account, and nothing about your screen is sent anywhere. It works the same on Windows, macOS, Linux, phones and TVs.