A careful inspection is easier when the display is clean and the room lighting is comfortable. Keep track of any questionable spot’s location and the colors where it stands out; those notes can help you explain what you saw to a seller or manufacturer.
How to use Dead Pixel Test
- Select Start Test to begin, then inspect the display from edge to edge, including its center, corners, and borders.
- Choose a color from Pattern mode: White, Black, Red, Green, Blue, 50% digital gray, Cyan, Magenta, or Yellow. Different backgrounds can make different visible irregularities easier to notice.
- Use Previous and Next, or the Left and Right keys, to move between patterns. Compare a suspicious spot in the same position across several colors rather than judging it from one view.
- For hands-free pattern changes, choose an Automatic interval of 2 seconds, 5 seconds, 10 seconds, or 15 seconds, then turn on Automatic mode. Press Space to switch automatic mode on or off. Reduced motion keeps progression manual.
- Select Fullscreen or press F to enter fullscreen. Press Escape to exit, or use Exit fullscreen. On a touchscreen in fullscreen, tap the left or right half to change patterns; on phones, an Exit button stays on screen.
- Select Reset or press R to reset the test. Stop if bright patterns cause discomfort.
When to use it
- Before a return window closes: Check a newly purchased display early, so you have time to raise a concern with the seller.
- When considering a used screen: Inspect a monitor, laptop, or phone in person and look for visible spots before deciding whether to buy.
- After setting up a new display: Make an initial visual check while getting familiar with the screen.
- When you notice a dot or mark: Compare its position on several colors to see which backgrounds make it easier to see.
- While comparing display settings: Look at the same patterns and areas under each setting, and note whether the spot’s appearance changes.
- For a quick phone or tablet check: Move through the solid colors and inspect the full screen rather than only its center.
Tips for a clearer inspection
Look steadily across each pattern and check the same areas each time. A suspicious spot may be obvious on one background and difficult to distinguish on another, so compare its position instead of relying on a single color. Note the pattern and location before moving on.
Dust or a smudge can look like a screen irregularity. If you see a mark, gently clean the display and check that area again. For a separate visual check aimed at pixels that appear stuck, try the Stuck Pixel Test.
Limits of Dead Pixel Test
Dead Pixel Test shows patterns for you to inspect; it cannot locate defective pixels automatically. It is a visual check, not a calibrated measurement, and browser scaling or display settings can affect how a pattern looks. A visible mark alone does not confirm a particular hardware fault.
If a suspicious spot remains visible across several colors, note where it appears and contact the screen’s seller or manufacturer for advice. For a precise diagnosis or measurement, professional equipment or manufacturer support is a better next step.