A bad pixel hides fine against a busy desktop. Open a white document or a dark photo and it stands out: a tiny dot that won’t match the screen around it. Flood the display with one solid color and it has nowhere to hide. This guide covers the browser test, the three pixel types, what you can actually fix, and when to send the screen back.
Tell a dead pixel from a stuck or hot one
Not every bad pixel is the same, and the type decides whether it’s worth trying to save.
A dead pixel gets no power. Its transistor has failed, so it stays black on every color and shows up as a black speck on white, red, green, or any bright fill. A dead pixel almost never comes back.
A stuck pixel still gets power, but a subpixel is frozen on one value. It glows red, green, or blue while the rest of the screen changes, and it stands out hardest against black. Stuck pixels are the ones with a real shot at recovery.
A hot pixel is rarer. All three subpixels fire at once and lock to white, so the dot burns bright against a dark field. It’s easier to spot than a dead pixel and harder to fix than a stuck one.
One more case. A pixel has three subpixels: red, green, and blue. Sometimes only one fails. That fault shows on a single color and vanishes on the rest, so cycling the whole set is the only way to catch it.
Run the dead pixel test
Start clean. A speck of dust or a smudge can look exactly like a dead pixel, so wipe the glass with a dry microfiber cloth before you trust what you’re seeing.
Open the dead pixel test and go full screen, so one solid color fills the display with nothing else on it. Click or press the arrow keys to step through the colors, or turn on Auto-cycle and let it rotate for you. On each fill, scan the whole screen slowly, corner to corner.
Get close. A single pixel is smaller than a grain of salt, so put your face near the glass or hold a phone camera to the screen and zoom in. Stuck and hot pixels give themselves away on the black fill, glowing where the rest of the screen stays dark. Flip to a bright fill and a dead pixel does the opposite, sitting there as a stubborn black dot. Work through white, red, green, and blue at a minimum so a single-color subpixel fault can’t slip past.
Make sure it’s really the screen
Before you treat a dot as a defect, rule out the cheap explanations. Dust mimics a dead pixel perfectly, so wipe the spot first. If it’s gone, you never had a defect.
If it survives the cloth, check that the panel is at fault and not the signal feeding it. Plug into a different cable or port, or run the test on another device. A mark that follows the picture from one input to the next lives in the panel. One that vanishes when you switch sources points at the cable or the graphics card instead, and that’s a far cheaper fix.
What you can actually fix
A stuck pixel sometimes recovers. A dead one almost never does, and no method reliably revives it. Put your time into the stuck ones.
The first method costs nothing. Open the stuck pixel fixer, go full screen, and drag its box of fast random color over the stuck spot. Flipping the subpixel through colors many times a second forces its transistor to toggle across its full range, which can jolt a frozen cell loose. Leave it running for 20 to 30 minutes, check the spot on a black screen, and run it again if the dot is still there.
The color noise box parks on each stuck pixel until the frozen subpixel breaks loose, then steps to the next.
If that does nothing, there’s the pressure trick, and it works on an LCD only. Power the screen off, fold a soft cloth over the exact spot, and press very gently for a few seconds while you turn it back on. That nudge can reseat the liquid crystal under a stuck cell. Light pressure only. Push too hard and you trade one stuck pixel for a patch of dead ones.
One warning. Do not press on an OLED panel. There’s no liquid crystal to reseat, and the organic layer takes permanent damage under pressure while the surface scratches or cracks. Stick to color cycling on OLED, or run the pixel-refresh routine many OLED monitors keep in their settings menu.
Claim the warranty before the window closes
Most people skip this step and regret it. Makers don’t promise a flawless panel. Most follow the ISO 9241-307 standard, which sorts displays into defect classes by how many bad pixels they’re allowed to ship. The common Class II permits, per million pixels, two always-on bright dots, two dead black ones, and up to five stuck subpixels before the panel qualifies as defective. Some premium screens carry a zero bright dot guarantee that covers even one. Your warranty lists the exact count it honors.
So test the moment a new monitor, laptop, or phone comes out of the box, while you can still send it back. Photograph any dot you find with a second phone or camera, because a screenshot saves the perfect framebuffer and never the broken pixel. A dead pixel caught in week one is a free exchange. The same dot in month six is a fight. The check pays off on a used display too, before you hand over any cash, where a hidden dead pixel is either a discount or a reason to walk.