Dead Pixel Checker
| What you saw | On black | On white | Verdict |
|---|---|---|---|
| Bright dot | glows | invisible | hot pixel - all sub-pixels stuck on |
| Dark dot | invisible | black | dead pixel - panel electronics |
| Fixed color dot | shifts | shifts | stuck pixel - one sub-pixel jammed |
| Dark blob, shifts with angle | any | any | dust - clean the glass, not a defect |
A dead pixel hides in normal content and stands out on pure color - which is why every proper screen test is just your panel showing solid red, green, blue, white and black, one fullscreen at a time, while your eyes walk the surface.
Bottom line: start the cycle, grab a soft cloth, wipe the dust off first, then scan each color slowly. Black exposes bright defects, white exposes dark ones, and the three primaries expose pixels stuck on a single sub-pixel - five colors, one minute, every class of defect.
The honest part: not every dark dot is a warranty case. A dead pixel (black on white) and a stuck pixel (one frozen color) are panel electronics; a dark blob that shifts when you tilt the screen or press the bezel gently is dust or a pressure mark under the glass - fixable by cleaning or time, and not a defect a manufacturer will swap a panel for.
How to use
- Clean the screen with a dry microfiber cloth first - dust is the number one false positive. Then press Start test and let the page go fullscreen; it cycles red, green, blue, white and black every three seconds, or click to advance early.
- On each color, sweep your eyes in rows from corner to corner. Black finds hot pixels (always lit) and bright dust; white finds dead pixels (always dark) and pressure marks; red, green and blue each expose pixels frozen on one sub-pixel.
- Press Esc or tap the exit corner to leave fullscreen, then classify what you saw with the table below before contacting support - screenshot the color and position (count columns from the left) because warranty desks ask for both.
Frequently asked questions
What is the difference between a dead, stuck and hot pixel?
A dead pixel shows black on every background because all three sub-pixels are off; a stuck pixel holds a single color (often red or blue) because one sub-pixel jams; a hot pixel glows white or bright on black because all sub-pixels are stuck on. Dead is the hardest to fix; stuck pixels sometimes yield to rapid color-cycling tools.
How many dead pixels does it take for warranty replacement?
Policies vary and are mostly stricter than people hope: many laptop makers allow a cluster of bright defects (commonly 3-7, or 1-2 within a small central zone) before a panel swap; some premium lines promise zero bright-dot panels. Check your manufacturer's policy page with the exact count and position from this test in hand - that is what the support agent will ask for first.
Can a stuck pixel be fixed at home?
Sometimes. Rapid full-screen color cycling for ten to thirty minutes revives jammed sub-pixels in a share of cases, and a gentle pressure massage through a cloth on the exact spot is the folk remedy that occasionally works - both are safe when brief. A permanently dead pixel does not respond to either; only a panel replacement changes it.
Why does my camera find spots my eyes miss, and the reverse?
A phone camera on the screen at high zoom catches sub-pixel defects smaller than your eye resolves at arm's length - but the camera adds its own hot pixels as noise. Use the camera to locate, then confirm with your naked eye at the fullscreen color; warranty claims are judged by what a person sees, not by sensor artifacts.