How to run the dead pixel test
- Wipe the screen with a dry microfiber cloth first. A speck of dust looks exactly like a dead pixel.
- Press Start dead pixel test. The screen fills with one solid color and the cursor hides.
- Scan the whole screen slowly, edge to edge. Then click, or press Space or →, for the next color. ← goes back and Esc exits.
- Found something? Press M and click the spot. Its position is saved to the defect list for your report.
On a phone or tablet, tap to advance and use the on-screen buttons, which reappear whenever you touch the screen. Many phones can’t hide the browser bar, so rotate to landscape and scroll the page slightly first.
Dead, stuck or hot pixel?
Each pixel is made of three sub-pixels: red, green and blue. The color of the dot, and the backgrounds it shows up on, tell you what failed.
| Defect | What you see | Best screen to spot it | Fixable? |
|---|---|---|---|
| Dead pixel | A black dot that never lights | White, red, green, blue | Rarely. The transistor has failed. |
| Stuck pixel | A red, green, blue, cyan, magenta or yellow dot that never changes | Black, then the other colors | Sometimes. Try the fixer. |
| Hot pixel | A white dot, all three sub-pixels always on | Black | Sometimes |
| Dead sub-pixel | A colored dot on white, for example cyan when red is dead | White | Rarely |
How to read each test color
- Black shows stuck and hot pixels as bright dots. It also shows backlight bleed and IPS glow. For a longer look, use the black screen tool.
- White shows dead pixels as black dots. A dot in a single color means one sub-pixel won’t light.
- Red, green and blue isolate the sub-pixels. On red, a black dot is a dead red sub-pixel (or a dead pixel). A yellow or magenta dot means the green or blue sub-pixel is stuck on.
- Gray shows dark and bright defects at once, plus blotchy uniformity (“dirty screen effect”).
- Gradient should be a smooth ramp. Visible steps or clouds point to the panel or its settings, not individual pixels.
Fixing a stuck pixel
Mark the pixel, then use the fixer: accept the warning, press Fix next to the defect (or open the fixer and drag the square over it) and let it run for 10 to 20 minutes. Rapidly switching the sub-pixels sometimes frees one that’s stuck. If it doesn’t work, try again with a longer session. Some stuck pixels never recover, and a dead (black) pixel won’t respond at all. Avoid pressing on the screen: it can create new defects and may void your warranty.
Returns and warranty
Test a new monitor, TV or laptop as soon as it arrives. Store return windows are often shorter than the warranty and usually easier. Manufacturers publish pixel policies that allow a small number of defects. Many are based on the old ISO 13406-2 Class II standard, which allows up to 2 always-lit, 2 always-dark and 5 sub-pixel defects per million pixels. Premium lines often promise “zero bright dots”. Use the report above (count, positions, screen size) and your photos when you contact support. Testing a new laptop? Also run the keyboard tester, and check a new high-refresh monitor with the refresh rate test.