How to use this test
- Clean your screen first. Dust and specks look exactly like dead pixels. Wipe the display before you start or you will chase smudges.
- Go fullscreen. Browser chrome hides part of the panel, and pixels hide in exactly the strip you cannot see.
- Step through every colour. A dead pixel stays black on all of them. A stuck pixel stays one colour on all of them. That difference tells you which you have.
- Try repair mode for stuck pixels. Rapid colour cycling sometimes frees a stuck sub-pixel. It cannot help a dead one, and the page explains why.
Dead or stuck? The distinction that matters
These get used interchangeably, and they are completely different faults with completely different outcomes.
| Fault | How it behaves | Cause | Fixable? |
|---|---|---|---|
| Dead | Black on every colour | Transistor has failed — no power reaching it | No |
| Stuck | One colour on every screen | Sub-pixel jammed on | Sometimes |
| Hot | Always white | All three sub-pixels stuck on | Rarely |
Each screen pixel is three sub-pixels — red, green and blue — and what you see depends on which of them are working. A pixel showing persistent red has red stuck on and the other two behaving. A pixel showing black has lost power entirely.
Stepping through solid colours makes this unambiguous, and it takes about twenty seconds. A dot that stays black on a white screen is dead. A dot that stays red on a green screen is stuck.
Why fullscreen matters
Browser toolbars, tabs and the taskbar cover a meaningful fraction of the panel — usually the top and bottom strips. Those are ordinary parts of the display and just as likely to have faults, so checking without fullscreen means not checking a real portion of your screen.
Clean the screen first, too. Dust, fingerprints and specks look convincingly like pixel faults, particularly on black, and people regularly panic over a speck.
Can stuck pixels really be repaired?
Sometimes. The mechanism is real rather than folklore: rapidly cycling colours forces the transistors driving each sub-pixel to switch state many times per second, and that repeated switching can dislodge a liquid crystal that has become stuck in one position.
Realistic expectations matter here:
- It works best on recently stuck pixels. A pixel stuck for a year is much less likely to recover than one that appeared last week.
- It takes time. Run it for at least ten minutes, and up to thirty, before concluding it has failed.
- It cannot help a dead pixel. There is no power reaching that transistor. Nothing displayed on screen changes that.
- It cannot damage a healthy screen. The panel is doing what it does normally, just quickly.
The gentle-pressure technique you will find elsewhere — pressing the stuck pixel with a soft cloth while the screen cycles — sometimes helps as well, but it carries real risk of causing further damage. We would not recommend it on a screen you care about.
A note on OLED
OLED panels rarely develop stuck pixels, because each pixel emits its own light rather than gating a backlight. What they can develop is burn-in: faint permanent shapes where static content sat for a very long time. That shows up on solid colours as a ghostly outline rather than as individual dots. If that is what you are seeing, it is a different fault and it is not repairable.
Related tests
The monitor test covers backlight bleed, uniformity, colour banding and measured refresh rate — worth running on any new display alongside this one.
Frequently asked questions
What is the difference between a dead pixel and a stuck pixel?
A dead pixel receives no power — its transistor has failed — so it stays black no matter what the screen displays. A stuck pixel is powered but jammed at one value, so it shows as a persistent red, green, blue or white dot. The distinction matters practically: stuck pixels are sometimes recoverable, and dead ones never are. Stepping through solid colours tells them apart in seconds.
Can a dead pixel be fixed?
No. A dead pixel means the transistor driving it has failed, and no software can restore power to a broken circuit. Repair modes, pressure techniques and every app claiming otherwise are addressing stuck pixels, not dead ones. If yours stays black on white, red, green and blue, it is dead and only panel replacement will change that.
Does stuck pixel repair actually work?
Sometimes, genuinely. Rapidly cycling colours forces the sub-pixel transistors to switch state thousands of times, which can dislodge a stuck liquid crystal. Success is real but far from guaranteed — it works best on recently stuck pixels and rarely on long-standing ones. Run it for ten to thirty minutes before deciding it has failed. It cannot damage a working display.
How many dead pixels before a warranty claim?
It depends on the manufacturer and the panel grade, and the thresholds are less generous than people expect. Many consumer monitors require three to five dead pixels before a replacement is authorised, and some allow more. Premium and professional panels often carry a zero-tolerance policy. Check your specific model’s pixel policy before contacting support, and photograph the fault on a solid background.
Why do I see faint dots on the grey screen only?
That is usually dust on the screen surface rather than a pixel fault, and grey shows it up best. Clean the display and re-check. If a dot persists after cleaning and only appears on grey, it may be a slightly weak sub-pixel rather than a fully stuck one, which is generally not covered by warranty.
Does this test work on a phone or TV?
Yes. It is just full-screen colour, so anything with a browser works. On a TV, opening this page in a built-in browser or casting it works well. OLED panels rarely have stuck pixels but can show early burn-in, which appears as faint persistent shapes on solid colours rather than as individual dots.