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Check for dead pixels, bright spots and dark spots
Why Choose Our Dead Pixel Test
12-color fullscreen + keyboard/touch shortcuts — complete a professional dead pixel scan in 3 minutes
12-Color Pure Test
Covers white, black, red, green, blue, cyan, magenta, yellow, orange, and 3 grey levels to ensure no defective pixel goes undetected.
Fullscreen Immersive
One-click fullscreen mode eliminates UI distractions. Arrow keys, spacebar, or swipe gestures cycle colors quickly and smoothly.
Zero Privacy Risk
Pure frontend CSS rendering. No camera, sensors, or data uploads. All resources are released when the page is closed.
What Are Dead Pixels
Dead pixels are pixel units on a display panel that fail to display colors correctly, typically appearing as fixed bright spots, dark spots, or stuck color points.
Bright Pixel (Stuck Pixel)
A pixel permanently stuck in an illuminated state, appearing as a constantly glowing white or colored dot on dark backgrounds. Bright pixels are usually caused by a sub-pixel stuck in the "on" state and may sometimes be recoverable using pixel repair tools.
Dead Pixel
A completely failed pixel that remains black regardless of displayed content. Most easily detected on light or pure white backgrounds. Dead pixels are typically hardware-level damage and generally cannot be repaired.
Stuck Pixel
A pixel stuck at a fixed color (red, green, blue, or a combination) that doesn't change with the image. Unlike dead pixels, stuck pixel sub-pixels still respond and have a chance of recovery through rapid color cycling.
How to Test for Dead Pixels
Follow these steps to systematically check for every type of defective pixel
Prepare Environment
Set screen brightness to maximum, turn off night mode/blue light filter. Testing in a dimly lit environment yields the best results.
Fullscreen Color Cycle
Click a color preview to enter fullscreen. Use arrow keys to cycle through all 12 solid colors. Carefully scan the entire screen at each color.
Focus on Key Areas
Dead pixels are most common at screen edges and corners. Slowly scan the entire panel for each color, paying special attention to bright spots on dark backgrounds and dark spots on light backgrounds.
What Causes Dead Pixels
Manufacturing Defects
During LCD panel production, TFT transistors or OLED emissive layers may sustain microscopic damage, causing individual pixels to be defective from the factory.
Physical Pressure
Compression during shipping, aggressive cleaning, or contact with sharp objects can damage liquid crystal alignment or OLED organic materials.
Electrostatic Damage
Electrostatic discharge (ESD) in dry environments can destroy drive transistors, causing permanent pixel failure.
Natural Aging
Over extended use, some pixels' drive circuits or emissive materials degrade, especially in areas that frequently display high-brightness content.
Industry Dead Pixel Standards
Different manufacturers and panel grades have varying tolerances for dead pixels
ISO 13406-2 Class II
Allows up to 2 bright + 2 dark + 5 stuck pixels (per million pixel panel)
Apple Policy
Any visible dead pixel qualifies for replacement (zero tolerance)
Dell Premium Panel
Zero bright pixel tolerance; 1-5 dark pixels allowed (varies by model and panel size)
General Consumer
Class II standard: ≤3 bright, ≤3 dark, ≤7 stuck pixels considered acceptable
Dead Pixel Detection FAQ
Q.Can dead pixels be repaired?
Bright and stuck pixels have a chance of recovery through rapid color flashing programs. Dead pixels (completely failed) generally cannot be fixed via software and require panel replacement. Try running an online pixel repair tool for 30-60 minutes first.
Q.Can I return a new screen with dead pixels?
Depends on brand policy. Apple and Dell premium lines typically have zero tolerance. Most brands follow ISO 13406-2 Class II standards. We recommend testing immediately upon receiving your new screen and filing within the return window.
Q.Why are 12 different colors needed?
Each pixel consists of red, green, and blue sub-pixels. Using only black and white can only detect completely dead pixels. RGB primaries + complementary colors can detect individual stuck sub-pixels. Grey tones also help reveal uneven brightness differences.
Q.Does this work on phone screens?
Absolutely. The tool supports fullscreen mode and is compatible with phones, tablets, laptops, desktop monitors, and TVs. Mobile users can swipe left/right to change colors.
Q.What's the difference between dead pixels and OLED burn-in?
Dead pixels are single pixel-level hardware defects appearing as fixed abnormal points. Burn-in is uneven aging across large areas of an OLED panel, appearing as ghost images or color-shifted regions. Both can be detected with solid color tests, but causes and remedies are completely different.
Q.What should I do after finding dead pixels?
1) Photograph and document pixel location and count; 2) Check your brand's dead pixel return policy; 3) For bright/stuck pixels, try pixel repair tools first; 4) If within warranty and exceeding allowed limits, contact support for replacement or repair.
Testing Tips
Max Brightness
Set screen brightness to 100% before testing. Some defective pixels are hard to spot at low brightness.
Disable Filters
Make sure night mode, blue light filter, HDR enhancement, and other post-processing effects are turned off to avoid interfering with test results.
Dark Room
Testing in a dimly lit environment yields the best results, especially when checking for bright pixels on pure black backgrounds.
Scan Patiently
Stay on each color for at least 5 seconds. Slowly scan the entire panel from top to bottom, left to right.
Start Testing Your Screen
12-color fullscreen test, complete dead pixel scan in 3 minutes. Essential for new device inspection and used device verification.