How to check a new screen for dead pixels
To check a screen for dead pixels, fill it with solid black, white, red, green and blue, and look closely for a dot that does not match the colour around it. Do this as soon as you unbox the device, while the return window is still open. Use still colours only. A good check never flashes or strobes, and the reason is explained below.
Dead pixel testSpot on my new screen?OpenDead, stuck and hot pixels
Terms vary between manufacturers and reviewers, so here are the usual meanings.
- A dead pixel is always off. It shows as a dark dot on a white or coloured background, because it never lights.
- A stuck pixel is always on, usually in one colour. It shows as a red, green, blue or white dot on a black background, because one of its coloured parts stays lit.
- A hot pixel is a bright stuck point, often white, that shows most clearly on dark screens. The term is used loosely for displays, and it is more common for camera sensors.
Each pixel is made of smaller red, green and blue parts, called subpixels. When one subpixel fails to switch, a solid colour reveals it, because the dot no longer matches the surrounding colour. That is why a check with several solid colours works better than a glance at one image.
How to run the check
- Clean the screen with a dry microfibre cloth. Dust and smears can look like defects.
- Open the dead pixel test, or any solid-colour page, and make it full screen.
- Show each colour in turn: black, white, red, green and blue.
- For each colour, look closely, then from normal viewing distance. Check the edges and corners, which are easy to miss.
- If you find a defect, note its colour and position, and take a photo of the screen showing it, with the date visible.
The same steps work on phones and laptops. Turn the brightness up for the check. To see the exact size and pixel ratio of the screen you are testing, the screen resolution check shows both.
Use this to read what you see:
| Background | What a defect looks like |
|---|---|
| Black | A bright dot, which is a stuck or hot pixel |
| White | A dark dot, which is a dead pixel |
| Red, green or blue | A dot of another colour, or a dark dot |
A real pixel defect stays in the same place on every solid colour, and it does not move when you wipe the screen. A speck of dust or a smear moves or disappears, so wipe again before you record anything. Run the check in a dim room too, because faint defects are easier to see against black.
Why check quickly
Return rules vary by retailer and by country, and so do the rules for defective screens. Some sellers accept a screen with defects only within a short return window. Some manufacturers publish a defect policy that sets how many defects are needed before they will replace a panel, and the thresholds differ between makers. Read the policy before you buy, and test in the first days, while returning is simplest. Keep the packaging until the screen passes. A dated photo of any defect helps if you need to make a claim.
Claims that do not hold up
You may see advice that massaging the screen, pressing hard on a stuck pixel, or running a fast-flashing video will repair it. That advice is unreliable. No method reliably repairs a faulty subpixel, and pressing on a panel can crack it or cause new damage.
Flashing tools cycle colours quickly across the whole screen, and fixmint does not offer one. Rapid flashing can trigger seizures in people with photosensitive epilepsy, and there is no reliable evidence that it repairs anything. A still-colour check gives you the same information about your screen without that risk.
What to do with a defect
Compare what you found with the seller's policy. If the defect is within the return window and the policy, arrange the return with your photo and the date. If it falls short of the replacement threshold, ask about a replacement anyway, because some sellers handle cases individually. If the screen looks fine on the first day, check again after a week of normal use, because some faults appear later. If the same device also has a keyboard fault, keyboard keys not working covers that check.
Quick answers
Is one dead pixel a reason to return a screen?
It depends on the seller's and the manufacturer's defect policy, which varies. Check it before you buy, and test early.
Can pressing or flashing fix a dead pixel?
Not reliably. Pressing can damage the panel, and flashing can trigger seizures, so use only still-colour checks.
Should I check a phone the same way?
Yes. Use the same solid colours, make the screen full screen, and turn the brightness up.
