Dead Pixel Test
Test your screen online for dead, stuck, or warm pixels with full-screen color backgrounds, display uniformity checks, and a built-in stuck-pixel reviver tool.
๐ Runs entirely in your browser โ nothing is uploadedHow to test your monitor for dead and stuck pixels
A dead pixel test helps you inspect computer monitors, laptop panels, tablets, and smartphone displays for defective liquid crystals. Modern high-resolution screens pack millions of tiny sub-pixels: a standard 1080p display contains over 6.2 million individual red, green, and blue sub-pixels, while a 4K display features nearly 25 million. Manufacturing imperfections or mechanical trauma can cause individual transistors to fail.
This online tester runs completely inside your web browser without downloading any external software or extensions. Launching fullscreen mode displays clean, uncompressed solid colors edge-to-edge. A pure black screen exposes stuck and hot pixels that glow when they should be dark, while a pure white screen immediately reveals dead pixels that fail to illuminate. Cycling through individual red, green, and blue backgrounds isolates individual sub-pixel anomalies that might go unnoticed during daily browsing.
Understanding pixel defects: dead, stuck, and hot
Display flaws generally fall into three distinct categories based on electrical and crystal behavior:
- Dead Pixels: The driving thin-film transistor (TFT) has failed to deliver electrical current, leaving the pixel in a permanent dark state. A dead pixel stands out as a tiny black square against light or white content.
- Stuck Sub-Pixels: One of the three primary color sub-pixels (Red, Green, or Blue) is physically jammed in an energized position. It shines brightly against dark backgrounds but blends in on matching colored screens.
- Hot Pixels: All three sub-pixels remain fully open, producing an intense white dot that remains visible across dark movies and games.
Checking display uniformity and IPS glow
Beyond individual pixel defects, modern LCD, OLED, and Mini-LED panels can suffer from uneven illumination. Testing with the 50% neutral gray screen reveals panel uniformity variations, dirty screen effect (DSE), and banding. Inspecting the pure black screen in a dimly lit room highlights backlight bleed around the bezel edges and IPS glow caused by liquid crystal polarization angles.
Using the stuck pixel reviver tool
While truly dead pixels cannot be restored by software, stuck sub-pixels can often be jarred back into normal operation. The built-in Stuck Pixel Reviver tool generates rapid, high-frequency alternating color cycles at 30 to 60 Hz. Position the draggable flashing box directly over the stuck pixel and allow it to run for 10 to 15 minutes. The rapid voltage shifts stimulate the sluggish liquid crystals, encouraging them to regain proper alignment.
How to use
- Clean your displayGently wipe away dust and fingerprints with a soft microfiber cloth before starting so specks are not mistaken for dead pixels.
- Launch fullscreen modeClick 'Launch Fullscreen Test' to expand solid test colors across your entire monitor with zero distractions or browser chrome.
- Inspect each primary colorPress Space, click, or use arrow keys to cycle through black, white, red, green, blue, and gray backgrounds.
- Identify defect typeLook for dots that remain black on bright screens (dead pixels) or glow red/green/blue on a pure black screen (stuck sub-pixels).
- Try the stuck pixel fixerIf you locate a stuck colored pixel, position the high-frequency flashing reviver box over it for 10โ15 minutes.