Stuck Pixels vs. Dead Pixels: What Is the Difference?
Learn how dead pixels, stuck pixels, and subpixel faults behave on different color fields, and how to document the result without guessing.
The words “dead pixel” and “stuck pixel” are often used interchangeably, but they describe different visible behavior. A dead pixel usually stays dark when the surrounding field is bright. A stuck pixel remains lit or fixed to a color because one or more subpixels are not changing as expected. The distinction is useful when you test a new screen, even though the final decision still depends on the seller’s policy.
Think in pixels and subpixels
A pixel is a small picture element made from red, green, and blue subpixels. By varying those subpixels, the panel produces the colors you see. If the complete pixel does not emit light, it can look black on a white field. If one subpixel is stuck on, a tiny red, green, or blue point may remain visible while the rest of the image changes.
The visible label is not a repair diagnosis. LCD, OLED, and other panel designs behave differently, and a browser cannot inspect the underlying drive electronics. Use the terms to describe the observation, not to promise a particular cause.
Use fields that ask different questions
Open Screen Tester and work through the fields in a fixed order:
- White reveals dark points and dim pixels.
- Black reveals points that remain bright or colored.
- Red, green, and blue isolate a subpixel that stays on or fails to light.
- Gray fields reveal weak contrast, tint, or a point that is difficult to see on pure white.
Suppose a point is black on white, red, green, and blue, then remains black on gray. That is consistent with a dark or dead-looking pixel. Suppose it appears red on white, black, green, and blue. That is consistent with a red subpixel stuck on. The example describes the pattern; it does not prove which component failed.
Check position, not just color
Change the field while watching the suspected location. A panel defect stays attached to the same physical point. A dust particle may move when you clean the surface, and a reflection may change when you move your head. A browser artifact can disappear when the page repaints or when a window moves.
Keep your browser at its normal zoom and use fullscreen so a toolbar or taskbar does not hide an edge. Look close enough to confirm the point, then return to a normal viewing distance. Viewing angle can change the appearance of dark areas on some panels, so check from the position where you normally sit.
Do not press or run risky “repair” loops
Pressure is not a safe diagnostic. It can mark the panel, damage a coating, or create a new fault. Rapid-flashing repair pages are also not a guaranteed fix and can be uncomfortable to view. First document the original behavior; changing the panel before you record it can make a return conversation harder.
If a seller asks whether the pixel is dead or stuck, send the exact fields on which it appears and disappears. “Visible as a red point on white and black; absent on red” is more useful than a label alone.
Compare the result with the policy
Pixel policies may count dark pixels, bright pixels, and subpixel faults differently. Some distinguish the center from the edge; some depend on panel class or product line. Read the written policy for the exact model and keep your photos, order date, and test notes together.
The practical conclusion is simple: use contrasting fields to classify what you can see, then use the policy to decide what to do. The browser test provides repeatable evidence, not a promise that a manufacturer will accept a claim.