FreeHow the dead pixel test works
Each pixel is made of red, green and blue parts. When the whole screen shows one solid colour, every pixel should look exactly the same, so any faulty one stands out against it. Cycling through black, white, the three primary colours and their mixes gives each part of each pixel a chance to show a fault.
What you might find
- Dead pixel: stays black on every colour, and is easiest to see on white. It gets no power, and usually can't be repaired.
- Stuck pixel: stays one colour, such as red, green or blue, whatever is shown. Most visible on black or a contrasting colour. These sometimes recover.
- Hot pixel: stays bright white, and stands out on black.
- Dust or a scratch: moves or blurs when you look from a different angle, or wipes away. A real pixel fault stays sharp and in the same spot.
Found one? What to do next
- Note where it is and which colours show it, and take a close-up photo.
- Check the return window. If the screen is new, many shops will swap it within the first few weeks.
- Read the maker's pixel policy. Warranties often allow a small number of faulty pixels before a replacement is offered.
- For a stuck pixel, give it time. Some come back after a few hours of normal use, or after the display is switched off overnight.
Frequently asked questions
Does this work on phones and TVs?
Yes. On a phone, tap the screen to change colour. On a smart TV, open this page in the TV's browser, or cast a browser tab to it.
The test isn't filling my whole screen.
Some browsers, including Safari on iPhone, don't allow websites to go full screen. Rotate the phone and hide the browser bars as far as possible, or check the edges separately.
Can this page fix a stuck pixel?
No. This page is for finding faulty pixels only. Rapidly flashing colours are sometimes suggested as a fix, but they don't help dead pixels and can be unsafe for people sensitive to flashing light.