Dead Pixel Test
Fill your screen with pure colors to find dead and stuck pixels, then try to fix the stuck ones.
Runs in your browser. Nothing you enter is uploaded.
Fills the screen with 6 colors in turn. Click or press → for the next one, Esc to stop.
Check your screen for bad pixels
Click Test my screen. It fills the screen with one color at a time: look over each one slowly, then pick what you saw.
Stuck pixel fixer
Flashing colors. Don’t use the fixer if you or anyone watching has photosensitive epilepsy, and look away while it runs.
It flashes a small square very fast. Drag it over the stuck pixel and leave it there; it stops by itself when the time is up.
How to use Dead Pixel Test
- Clean the screen with a dry cloth so dust isn’t mistaken for a pixel, and set the brightness to normal.
- Click Test my screen. The screen fills with black, white, red, green, blue and gray in turn.
- Look over each color slowly from about an arm’s length, then click or press → for the next one.
- Pick what you saw to get the diagnosis and the fix.
- For a stuck pixel, run the stuck pixel fixer with the flashing square over it for 10 to 20 minutes.
How it works
Each pixel is three tiny lights: red, green and blue. The test fills the whole screen with one pure color at a time, so every pixel should show exactly that color. A pixel that doesn’t stands out as a dot. Nothing is recorded or sent, and the test works on monitors, laptops, TVs (through a computer or a TV browser) and phones.
| Color | What it shows |
|---|---|
| Black | Pixels stuck on, and light leaking at the edges (backlight bleed) |
| White | Dead pixels, as black dots |
| Red, green, blue | Pixels stuck on another color: a green dot on red, for example |
| Gray | Uneven patches, smudges and darker corners |
On a phone, turn the brightness up and hold it still. On iPhones, which can’t put a page in full screen, the color fills the browser window; rotate the phone to see more of the screen at once.
Dead, stuck or dirt?
| What you see | What it is | Can it be fixed? |
|---|---|---|
| Black dot on every color | Dead pixel: it gets no power | Rarely. Check the warranty. |
| Red, green or blue dot | Stuck pixel: one part stays on | Sometimes, with the fixer |
| White dot on black | Stuck bright pixel: every part stays on | Sometimes, with the fixer |
| Light at the edges on black | Backlight bleed or IPS glow | Not a pixel fault; bad bleed is a warranty issue |
| Soft spot that moves when you wipe | Dust or a smudge on the surface | Yes: clean the screen |
Fixing a stuck pixel
The fixer flashes a small square through red, green, blue, white and black many times a second. Over the stuck pixel, that can get it working again.
- Find the pixel on the color where it shows best, then open the fixer.
- Drag the square over the pixel. Arrow keys move it one pixel at a time; hold Shift to move ten.
- Leave it for 10 to 20 minutes and look away while it runs. It stops by itself.
- Test again. If the pixel is still stuck, run the fixer once or twice more, for up to an hour.
Some guides suggest pressing on the pixel with a cloth while the screen is on. That can create more dead pixels or crack the panel, so don’t.
Flashing warning: the fixer flashes fast. Don’t use it if you or anyone watching has photosensitive epilepsy.
Warranty and returns
Makers each set their own pixel policy: how many dead or bright pixels, and where on the screen, before they replace it. Before you contact them:
- Count the dead and stuck pixels and note where they are. Copy report adds your screen’s size and what you found.
- Take a photo of each one on the color where it shows best.
- If the screen is new, a store return is often simpler than a warranty claim.
Questions
How do I check my screen for dead pixels?
Clean the screen, click Test my screen and look over each color slowly: black, white, red, green, blue and gray. A dot that doesn’t match the color is a bad pixel. Dust and smudges have soft edges and move when you wipe the screen; a pixel stays sharp and in place.
What is the difference between a dead pixel and a stuck pixel?
A dead pixel gets no power, so it stays black on every color. A stuck pixel has one or more of its red, green and blue parts stuck on, so it shows as a red, green, blue or white dot. Stuck pixels can sometimes be fixed; dead pixels usually can’t.
Can a stuck pixel fix itself?
Sometimes, after hours or days of normal use. Flashing colors over it with the stuck pixel fixer for 10 to 20 minutes, a few times, frees some stuck pixels sooner. It doesn’t help dead pixels, and it doesn’t work on every stuck one.
Is the stuck pixel fixer safe?
For the screen, yes: it only changes colors, like any video. It flashes very fast, though, so don’t use it if you or anyone watching has photosensitive epilepsy, and look away while it runs.
Is a dead pixel covered by the warranty?
It depends on the maker’s pixel policy. Many replace a screen only above a set number of dead or bright pixels, and some replace it for a single bright pixel. Check the policy, and return a new screen within the store’s return window if you can.
How do I test for backlight bleed?
In a dark room, show black full screen at your usual brightness and look straight at it. Light leaking in from the edges or corners is backlight bleed. A glow that changes as you move your head is IPS glow, which is normal for IPS screens.
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Updated October 18, 2026 · Works in current Chrome, Edge, Firefox and Safari · Runs entirely in your browser