Test your screen for dead, stuck, or defective pixels. Works on monitors, laptops, tablets, and phones.
Test includes 9 solid colors: Black, White, Red, Green, Blue, Cyan, Magenta, Yellow, and Gray
Press F or Space to start • ← → to change colors • ESC to exitTap anywhere in fullscreen to change colors • Tap and hold to exit
A dead pixel test is a diagnostic tool used to identify defective pixels on LCD, LED, OLED, and AMOLED displays. This free online dead pixel checker works on all devices including desktop monitors, laptops, smartphones (iPhone, Android, Samsung Galaxy), tablets (iPad, Surface), and TVs. By displaying solid colors across your entire screen, you can easily spot dead pixels (permanently black), stuck pixels (fixed incorrect color), or hot pixels (always lit).
Our dead pixel tester supports multiple screen resolutions from 1080p to 4K and 8K displays, making it perfect for testing new monitors, gaming displays, professional photo editing screens, and mobile devices. The test uses pure colors (#000000 black, #FFFFFF white, #FF0000 red, #00FF00 green, #0000FF blue) that are scientifically proven to reveal pixel defects most effectively.
New Display Warranty: Test monitors, laptops, phones, and tablets immediately after purchase. Most manufacturers offer returns or replacements for displays with dead pixels within the return period.
Quality Control: Verify display quality before accepting delivery of expensive monitors, gaming displays, or professional equipment.
Troubleshooting: Identify if screen issues are dead pixels, stuck pixels, or other display problems like backlight bleeding.
Resale Value: Prove your display is defect-free when selling used monitors, laptops, or phones.
Perfect for testing computer monitors, laptop screens, all-in-one PCs, and external displays. The desktop mode fills your entire screen with solid test colors, making it easy to spot dead or stuck pixels on large displays. Ideal for 1080p, 1440p (2K), 4K, and 8K monitors from brands like Dell, LG, Samsung, ASUS, BenQ, and ViewSonic.
Specifically designed for smartphones and tablets with support for all modern aspect ratios: 16:9 (older phones), 18:9 (Galaxy S8/S9), 19.5:9 (iPhone X/11/12/13/14), 20:9 (modern Android), 21:9 (ultra-wide Sony Xperia), and 4:3 (iPad tablets). Test iPhone screens, Samsung Galaxy displays, Google Pixel, OnePlus, and all Android devices.
Completely black on all test colors. The pixel is permanently off and cannot be repaired. Most noticeable on white or bright colored backgrounds.
Display a fixed color (red, green, or blue) regardless of the test pattern. Sometimes fixable using pixel fixing software or pressure methods.
Always lit white or bright, most visible on black backgrounds. Common on OLED displays and camera sensors.
Start the test in fullscreen mode and cycle through different solid colors (black, white, red, green, blue). Dead pixels appear as black dots on colored backgrounds and don't change with the color. Stuck pixels show incorrect fixed colors. Look carefully at each color pattern to detect any abnormal pixels.
Dead pixels are completely black on all colors because the pixel is permanently off. Stuck pixels show a fixed color (often red, green, or blue) because one or more sub-pixels are stuck in the on position. Both are defects, but stuck pixels might be fixable with pixel fixing tools, while dead pixels usually cannot be repaired.
The mobile test lets you select your device's aspect ratio (16:9, 18:9, 19.5:9, 20:9, 21:9, or 4:3) to ensure the test area perfectly fits your screen. This is important because different phones and tablets have different screen proportions. Select your ratio, go fullscreen, and test each color for pixel defects.
The most important test colors are pure black (#000000), pure white (#FFFFFF), pure red (#FF0000), pure green (#00FF00), and pure blue (#0000FF). These colors make it easiest to spot dead or stuck pixels. Testing with all colors is recommended for thorough pixel detection on monitors, laptops, and mobile screens.