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Click Start full-screen test on the Img Stop Dead Pixel Test. The screen fills with black, white, red, green, blue, grey and gradient colours – press the arrow keys, Space or tap to switch. Look for dots that do not change. For a stuck pixel, read the warning and start the fixer: it flashes colours over the pixel for a few minutes.
About the Dead Pixel Test & Stuck Pixel Fixer
The Img Stop Dead Pixel Test checks a screen for bad pixels in a minute. It shows full-screen solid colours, grey levels and gradients one after another, so dead pixels (always black), stuck pixels (always red, green or blue) and hot pixels (always white) are easy to spot. It works on monitors, laptops, TVs with a browser, tablets and phones.
If you find a stuck pixel, the stuck pixel fixer can sometimes bring it back. It flashes rapidly changing colours in a small square that you drag over the pixel, or over the whole screen, for as long as you choose. The flashing only starts after you confirm the photosensitive epilepsy warning.
Key features
- Full-screen coloursBlack, white, red, green, blue, cyan, magenta, yellow, three greys and your own colour.
- GradientsHorizontal, vertical and colour spectrum gradients to check banding and uniformity.
- Easy controlsArrow keys, Space, Esc, or tap left and right on touch screens.
- Auto cycleChange colour by itself every 2, 3, 5 or 10 seconds.
- Stuck pixel fixerPixel noise or solid colour flashes in a movable square or full screen, with a timer.
- Safe by designClear epilepsy warning and nothing ever flashes until you press Start.
How to use the Dead Pixel Test & Stuck Pixel Fixer
- Clean the screen Wipe the screen so dust is not mistaken for a dead pixel.
- Start the test Click Start full-screen test. Your browser switches to full screen.
- Go through the colours Press → or Space, or tap, and look closely for dots that stay the same.
- Fix stuck pixels Read the warning, start the fixer, drag the square over the pixel and let it run.
Dead Pixel Test & Stuck Pixel Fixer at a glance
| Price | Free |
|---|---|
| Works on | Monitors, laptops, TVs, tablets, phones |
| Test colours | 15 colours and gradients |
| Fixer | Square or full screen, 10–60 flashes per second |
| Controls | Keyboard, mouse, touch |
| Privacy | Nothing is uploaded or installed |
When to use it
- Check a new monitor, laptop or TV within the return period.
- Test a used phone, tablet or screen before buying it.
- Find out whether a spot is a dead pixel, a stuck pixel or just dust.
- Try to revive a stuck pixel before sending a screen for repair.
- Check backlight bleed and uniformity on black and grey screens.
Tips for the best result
- Look at the screen from a normal distance first, then closer – a magnifier helps on phones.
- Black shows hot pixels and backlight bleed, white shows dead pixels, red, green and blue show stuck sub-pixels.
- Run the fixer for 10 to 20 minutes and repeat a few times; stuck pixels sometimes need hours.
- Dead pixels (always black) usually cannot be fixed by software – check your warranty.
Frequently asked questions
How do I check my screen for dead pixels?
Clean the screen, click Start full-screen test and go through all colours with the arrow keys, Space or a tap. A dot that stays black, white or one colour while the rest of the screen changes is a bad pixel.
What is the difference between a dead and a stuck pixel?
A dead pixel gets no power and stays black on every colour. A stuck pixel stays red, green, blue or a mix of them because one sub-pixel is always on. Stuck pixels can sometimes be fixed, dead pixels usually cannot.
Does the stuck pixel fixer really work?
Sometimes. Fast changing colours make the stuck sub-pixel switch on and off many times, which can free it. It works best on pixels that became stuck recently. Run it for 10–20 minutes, check, and repeat if needed.
Is the fixer safe?
The fixer flashes bright colours quickly. Do not use it if you or anyone who can see the screen has photosensitive epilepsy or is sensitive to flashing light, and do not look at the flashing area. Nothing flashes until you tick the warning and press Start.
Does it work on phones and TVs?
Yes. On touch screens, tap the right or left side to change colour. On TVs, open the page in the TV browser and use the arrow keys of the remote. Some phones, like iPhones, do not allow real full screen in the browser – the test then fills the browser window.
How do I exit the full-screen test?
Press Esc, or tap the screen and then the × button in the top corner.
Learn more
- MDN: Image file types – common image formats explained
Made and maintained by the Img Stop team.