Dead Pixel Test
Solid colors make dead and stuck pixels jump out in a way no wallpaper ever will. Clean the screen first, get about 20–30cm away, and scan slowly panel by panel while each color fills the display.
The 9 test colors
Each click advances to the next solid color. The full cycle:
What the colors are for
- Black — a pixel that stays lit on black is a bright stuck pixel, the most annoying kind on dark content.
- White — a pixel that stays black on white is a dead pixel.
- Red / Green / Blue — single sub-pixel faults only show on their own color, so each pure hue gets its own pass.
- Gray & mixed hues — confirm anything suspicious; a real defect never moves, dust does.
Before you blame the panel
Clean the screen first. Smudges and dust read as defects at close range, and half of all "dead pixel" scares are one or the other. Screenshot artifacts are not pixel faults either: if a suspicious dot shows up in a screenshot too, the fault is in your capture, not the monitor. One more thing worth knowing before you contact support: screenshots do not capture real dead pixels. Photograph the screen with a phone if you need evidence.
Dead or stuck, and why it matters
A pixel that is always black is dead: the cell itself has failed. One frozen on a single color is stuck, meaning the sub-pixel is jammed on. The distinction decides your next step. Stuck pixels sometimes respond to rapid color cycling or gentle pressure; dead ones never do. It also decides the warranty math. Many panel makers only replace after a threshold count of defects, and a few explicitly exclude stuck pixels entirely, so read the policy before you escalate. The dead pixel test guide covers the color-by-color procedure and how to argue the warranty case. Found a likely stuck pixel? The stuck pixel fix guide covers the revival attempts that are safe to try and the defect counts that make a warranty claim stick.
Frequently asked questions
What is the difference between a dead and a stuck pixel?
A dead pixel shows black on every color because its sub-pixels no longer light up at all. A stuck pixel is jammed on one color (usually red, green or blue) and is visible on white or black but not on its own color. Stuck pixels can sometimes be revived; dead ones rarely are.
How close should I look during the test?
About 20–30cm away, and clean the screen first: dust and smudges masquerade as defects surprisingly well. Let each solid color fill the screen and scan slowly, panel by panel, rather than staring at the center. Black finds bright stuck pixels, white finds dark ones, and the pure red/green/blue screens expose single-sub-pixel faults.
How many dead pixels count as a warranty defect?
It depends on the maker and the panel class. Many manufacturers follow ISO 13406-2 style classes: a common reading is that a handful of dead pixels on a high-resolution panel is "acceptable", while bright stuck pixels on dark backgrounds are often not. Check your manufacturer policy before claiming, and screenshot or photograph the defect against a solid color as evidence.
Can software really fix a stuck pixel?
Sometimes. Rapidly cycling colors at a stuck pixel can nudges a misaligned liquid crystal back into place, and it costs nothing to try. It does nothing for a truly dead pixel. If a stuck pixel survives a few hours of cycling, it is effectively permanent.
Can a dead pixel spread to the pixels next to it?
No. Each pixel is an independent cell; one failing does not damage its neighbors. What you are often really seeing is a cluster that failed together at the factory, or a growing bright spot that is heat or pressure damage. The practical difference: a single pixel that stays put is covered by whatever the panel policy says, while a spreading bright spot is worth pushing on regardless of count.
Why does the defect only show on some colors and not others?
Because a pixel is made of three sub-pixels — red, green and blue — and each can fail independently. A stuck blue sub-pixel is invisible on a blue screen and obvious on yellow. That is exactly why the test runs a full color cycle: a defect that hides on white but shows on cyan is still a real defect, just a sub-pixel one. See it on any single color and it counts.
Is OLED burn-in the same as a stuck pixel?
No. A stuck pixel is a single cell stuck on or off. Burn-in is a whole region of the panel that has aged unevenly and shows a ghost image on gray backgrounds. The test tells them apart: a stuck pixel is a single point on every solid color, while burn-in is a shape (a logo, a taskbar) that fades in and out as the gray level changes.
I found a line of pixels, not a single one. Is that a scratch or a fault?
A vertical or horizontal line of dead pixels is a separate fault — usually a failed display cable or driver chip, not damage. A scratch, by contrast, stays visible when you look at the panel from an angle and often catches the light. If it is a line, screenshot the solid-color screen and get to the warranty desk; line faults are much more likely to be replaced than single dead pixels.