How to check for dead pixels
- Clean the screen first, so dust is not mistaken for a pixel fault.
- Press Start dead pixel test. The screen fills with black.
- Look over the whole screen, then click or press the right arrow for the next colour. Check each one.
| What you see | On which colour | Likely fault |
|---|---|---|
| Black dot | White and all colours | Dead pixel (never lights up) |
| Bright red, green or blue dot | Black | Stuck sub-pixel (always on) |
| Dot missing on one colour only | Red, green or blue | Stuck or dead sub-pixel |
| White dot | Black | Hot pixel (all sub-pixels stuck on) |
Can you fix a stuck pixel?
Sometimes. A stuck pixel is often a liquid crystal that is slow to change, and fast flashing colours can get it moving again. Start the stuck pixel fixer, drag the flashing square over the spot, and leave it for 10 to 30 minutes. Read the flashing light warning first. Double-click the square or press Esc to stop.
A truly dead pixel, one that stays black on every colour, has a failed transistor and cannot be fixed with software. Gentle pressure with a soft cloth on a stuck pixel helps in some cases, but pressing too hard can damage the panel, so it is at your own risk.
Is a dead pixel covered by warranty?
It depends on the maker's pixel policy. Many monitor makers follow the ISO 9241-307 classes, which allow a small number of faulty pixels before a screen counts as defective. Some brands offer a zero dead pixel guarantee on premium models. Check the policy for your monitor, and test new screens right away, since many shops accept returns in the first days without question.
Frequently asked questions
Short answers to the questions people ask most about this test.
What is the difference between a dead and a stuck pixel?
A dead pixel is always off and shows black on every colour. A stuck pixel is always on in one colour and shows as a bright dot, most visible on black.
Does the stuck pixel fixer work?
It helps with some stuck pixels, mostly ones that appeared recently. Run it for 10 to 30 minutes. It cannot repair a dead pixel.
Can I test my phone or TV screen?
Yes. Open this page on the phone, or in the browser on your smart TV, and start the test. On a TV you can also cast or connect a laptop and run it in full screen.
How many dead pixels are acceptable?
It depends on the manufacturer. Many follow ISO 9241-307 pixel classes that allow a few faulty pixels on large screens. Check your monitor’s pixel policy.