Screen & Dead Pixel Test

What this test checks

• Black background for bright or stuck pixels
• White background for dark or dead pixels
• Red, green and blue backgrounds for subpixel color issues
• Gray background for uneven or off-color spots
• Full-screen or viewport fallback depending on browser support

How this test works

1. Clean the screen so dust is not mistaken for a bad pixel.
2. Start the screen test and inspect every area on each solid color.
3. Tap or click the background to move through the colors.
4. Exit the test and repeat any suspicious spot before drawing a conclusion.

If the test does not behave as expected

• A web page cannot automatically detect a physical dead pixel because it cannot see the display panel itself.
• If full-screen mode is unavailable, the test still works in the browser viewport but browser controls may cover part of the screen.
• Dust, screen protectors, reflections and fingerprints can look like pixel defects; clean the display and retest.
• If a spot appears only on one color, repeat red, green and blue to distinguish a color-subpixel issue from dust or image content.

Note: This is a visual inspection aid. It cannot automatically confirm a panel defect or distinguish every hardware cause.