Dead pixel test for monitors and screens.

How this test works

Cycle through solid colors and inspect every part of the panel at a comfortable viewing distance.

1. Prepare the display using the checklist below.
2. Select Start test and allow fullscreen mode if your browser asks.
3. Use the arrow keys, on-screen controls, or click the pattern to move through the test.
4. Exit the runner and save a local observation if useful.

Before you begin

• Clean the screen gently
• Set browser zoom to 100%
• Use a comfortable brightness

What to look for

• Dark points on white or colored screens
• Bright points on a black screen
• Marks that remain in the same position

Compare a suspicious pixel with common lookalikes

Illustrations only: these are enlarged diagrams, not photographs, live test results, or diagnostic thresholds. Use the full-screen test to inspect your own display.

Check a phone or monitor without missing an area

1. Clean the screen using the maker’s instructions, then use native resolution and normal brightness. On a monitor, start with 100% browser zoom.
2. Start the test and inspect black, white, red, green, and blue in order. Scan the edges as well as the center, first from a normal distance.
3. Use the visible Previous pattern and Next pattern controls, arrow keys, or a tap on the pattern. If fullscreen is unavailable, only the uncovered window area is testable.
4. Record the point’s position and the backgrounds on which it appears. A screenshot captures software output; a camera photo may help locate a physical point but can distort it.

On a phone, rotate it and repeat briefly if browser controls cover an edge. Do not apply pressure, run flashing repair loops, or assume a visual observation meets the maker’s warranty criteria.

Read dead versus stuck pixels for classification, or follow the pixel inspection and documentation guide. A larger patch belongs in the uniformity check.

Use each solid color for a different clue

Start on black and scan the entire panel for points that remain bright. Switch to white and look for dark or strongly tinted points. Red, green, and blue help you see whether an individual color channel is behaving differently. Work across the screen in a deliberate pattern instead of staring only at its center. Inspect first from your normal viewing position, then move closer to verify a specific point. A tiny spot that appears only when your face is inches away may have a different practical impact from one visible during everyday work.

Keep track of whether the suspicious point stays in the same physical location as the background changes. A stuck subpixel may be easiest to see on one or two colors; a bright point can stand out against black; a dark point often shows against white. The pattern does not identify an electrical fault. It gives you repeatable visual evidence. If the spot moves when you change your viewing angle or wipe the surface using the maker’s guidance, dust, reflections, or a surface mark deserve another look before you call it a defective pixel.

Rule out lookalikes without stressing the panel

Use native resolution and 100% browser zoom so the pattern is presented consistently. Fullscreen removes most interface clutter; if fullscreen is unavailable, inspect the visible area in the window and account for browser borders. Clean the screen gently with the display turned off first. Do not press, massage, or rub a suspected pixel. Pressure can create damage or temporary color changes that make the original observation harder to interpret. If a mark is part of a larger patch or band rather than a point, the screen uniformity page is a more suitable follow-up.

A screenshot records the picture produced by software, not the light from a physical pixel. It is useful for checking whether a mark is already in an image or app, but it cannot prove a panel defect. A camera photo can document a location, yet focus and moiré may distort a one-pixel detail. Note the colors on which the point appears, its approximate position, the display model, and whether you also notice it in normal content. That description is often more useful than a dramatic close-up photo alone.

Decide what the observation means for you

A pixel pattern is a screening tool, not a pass-or-fail warranty judge. Display makers and retailers use different rules for bright points, dark points, location, count, and purchase period. If you recently bought the screen, check the current terms for your model and region before the return window closes. Repeat the check at a comfortable brightness and viewing distance, then ask whether the point interrupts the applications, games, or video you actually use. A defect visible only under an extreme test may warrant a different decision from one visible on ordinary backgrounds.

If you need to distinguish a dark pixel from a colored stuck subpixel, compare all five fields again and use the how-to guide for a step-by-step record. Do not assume a web pattern can repair a pixel or that a rapidly flashing routine is safe or effective. DisplayCheck does not upload your observation by default; the value of this test is that it helps you describe a small, fixed visual anomaly clearly enough to decide whether you want a second opinion or support from the manufacturer.

Frequently asked questions