Does my screen have dead pixels?
Run the fullscreen test below and look closely at each flat colour. A pixel that stays black on every colour is dead; one that stays lit in a single colour is stuck. Checking several colours matters, because a faulty pixel is invisible against a background of its own colour.
The screen cycles through black, white, red, green and blue. Look closely for pixels that stay black (dead) or keep showing the wrong color (stuck). Use arrow keys to change color and Esc to exit.
This runs locally in your browser. No device data is uploaded.
Dead, stuck, and which one you have
A dead pixel receives no power and stays black no matter what is displayed, so it shows up as a dark dot on the white and coloured screens. A stuck pixel is powered but locked to one colour, so it disappears on its own colour and glows against the others.
The distinction matters because stuck pixels sometimes recover and dead ones never do. It is also what warranty policies tend to hinge on, since a bright stuck pixel on a dark screen is far more distracting than a dark dot.
Can they be fixed?
Sometimes, for stuck pixels. Rapidly cycling colours in that area of the screen occasionally frees one, and gentle pressure through a soft cloth with the screen on is the other commonly suggested trick. Neither works reliably, and pressing hard risks spreading the damage.
A truly dead pixel cannot be revived. At that point the question is whether your warranty covers it — many require several faulty pixels before they accept a return, and the threshold varies by manufacturer and panel grade, so check the policy for your specific model.
Checking a phone or a screen you are about to buy
The test works on any device with a browser, so it is worth running on a phone, and worth running in a shop before you walk out with a new monitor. Turn the brightness up, inspect at a normal viewing distance first, then look closer at anything suspicious.
Clean the screen before deciding. A speck of dust looks remarkably like a stuck pixel, and it moves when you wipe it.
Frequently asked questions
- How many dead pixels does a warranty usually allow?
- It varies by manufacturer and panel grade, and many policies require several before accepting a return. Some treat a bright stuck pixel more seriously than a dark dead one. Check the policy for your model rather than a general figure.
- Does this work on a phone?
- Yes. Open the test on the device you want to check and go fullscreen. Phones are worth checking after a drop even when the glass looks intact.
More about this test
The full dead pixel test page covers how the test works and what the common faults look like.
Open the Dead Pixel Test →