Test Your Screen for Dead Pixels Online
Free online screen dead pixel checker — no install, no sign-up. Detect dead pixels, backlight bleed, and color uniformity issues on OLED, LCD, and phone displays with 20+ full-screen test patterns.
Start testing your display instantly
Solid Color Tests
Full-screen red, green, blue, white, yellow, cyan, magenta, and black patterns to isolate sub-pixel defects and detect dead or stuck pixels.
Line & Grid Patterns
Horizontal, vertical, diagonal lines and dot matrix patterns to reveal signal interference, display flickering, and rendering artifacts.
Contrast Gradients
Dark gradient blocks with subtle brightness steps to evaluate your display's contrast ratio and near-black shade discrimination.
All Display Types
Works on OLED, QD-OLED, LCD, IPS, VA, AMOLED, and CRT screens. Test monitors, TVs, laptops, tablets, and smartphones.
Comprehensive Online Screen Dead Pixel Checker
This free online screen test displays full-screen color patterns and line grids so you can spot dead pixels, backlight bleed, color uniformity issues, and display geometry problems in seconds — no software installation required.
20+ Test Patterns Included
Each pattern reveals different display issues
Complete Guide to Online Screen Dead Pixel Testing
“Dead pixels and backlight bleed are among the most common display defects. Our free screen test tool helps you identify these issues quickly using full-screen color and pattern tests.”
Welcome to the most comprehensive free online screen dead pixel checker. Whether you just bought a new monitor, want to verify a used TV, or check your phone screen, our tool detects dead pixels, stuck pixels, backlight bleed, and display uniformity issues with 20+ full-screen test patterns — no sign-up required.
How to Use This Free Screen Dead Pixel Checker
Using our online screen test is simple. Follow these steps to perform a complete display quality check:
- Click "Start Test Now" to enter fullscreen mode for the most accurate results.
- Navigate through test patterns using arrow keys, mouse scroll, or click anywhere.
- On each solid color pattern, look carefully for black dots (dead pixels) or mismatched colors (stuck pixels).
- Check line and grid patterns for any distortion, flickering, or convergence misalignment.
- Use the contrast gradient test to verify your display can distinguish subtle shade differences.
Solid Color Patterns for Dead Pixel Detection
Our tool provides 8 solid color backgrounds — red, green, blue, white, black, yellow, cyan, and magenta. Dead pixels appear as tiny black dots that don't illuminate, while stuck pixels remain a fixed color. By cycling through all colors, you can isolate exactly which sub-pixels are defective on your LCD, OLED, or phone screen.
Line Patterns for Signal Interference & Geometry Testing
Horizontal, vertical, and diagonal line patterns at 1px and 2px widths reveal signal interference, display flickering, and rendering artifacts. The square grid and dot matrix patterns help verify display geometry and pixel alignment. Color convergence patterns check that red, green, and blue sub-pixels are properly aligned across the entire screen, especially at the edges.
Contrast Gradient Test for Display Quality Evaluation
The dark contrast gradient test displays subtle brightness steps from near-black to slightly lighter shades. Professional-grade monitors can distinguish all blocks, while consumer displays may struggle with the darkest rows. This test is critical for evaluating your display's suitability for photo editing, movie watching, and other contrast-sensitive tasks.
Important Note on Display Testing
This testing tool will not cause any damage to your display equipment. It simply displays standard colors and patterns at normal brightness levels. However, it cannot replace professional calibration equipment. Test results are for reference only. Display equipment contains high voltage components — non-professionals should not attempt to repair display devices by themselves.
Supported Display Technologies
This online screen test works on all major display technologies and device types:
OLED / QD-OLED / AMOLED
Perfect for checking true black levels, burn-in marks, and color uniformity on premium OLED TVs and smartphone AMOLED screens.
LCD / IPS / VA
Ideal for detecting backlight bleed, stuck pixels, and IPS glow on desktop monitors, laptops, and LCD TVs.
Phones & Tablets
Test any smartphone or tablet screen for dead pixels and color accuracy — works on both iOS and Android devices.
This free screen dead pixel checker runs entirely in your browser with no download or sign-up required. Regular display testing helps you catch defects early and can provide evidence for warranty claims with manufacturers.