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Kordu Tools
Gaming Runs in browser Updated 30 Mar 2026

Dead Pixel Test

Test your monitor for dead or stuck pixels with fullscreen solid color screens. Includes a stuck pixel fixer that rapidly cycles colors to try to revive unresponsive pixels.

How It Works

This test fills your screen with solid colours so you can inspect for defective pixels. A dead pixel stays black on every colour. A stuck pixel shows the same colour regardless of background. Use the fullscreen test to cycle through each colour, then try the pixel fixer if you find a stuck pixel.

Test Colours

Stuck Pixel Fixer

Rapidly flashes colours to help unstick a stuck pixel. Position the flashing square over the affected pixel for best results.

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How to use Dead Pixel Test

  1. Launch the fullscreen test

    Click 'Start Fullscreen Test' or select a specific color to begin. Your screen fills with a solid color and your browser enters fullscreen mode.

  2. Inspect each color screen

    Click anywhere or press any key to cycle through black, white, red, green, blue, and grey. Look carefully across the entire screen for any pixel that doesn't match the background.

  3. Identify pixel issues

    A dead pixel stays black on every color — it appears as a tiny permanent dark dot. A stuck pixel shows the same color regardless of background. Note the position of any defective pixels.

  4. Run the stuck pixel fixer

    If you find a stuck pixel, exit the color test and activate the Stuck Pixel Fixer. Position it over the affected area and run it for five to ten minutes to attempt recovery.

Dead Pixel Test FAQ

What is a dead pixel?
A dead pixel is a display pixel that has permanently failed and appears as a tiny black dot regardless of what color the screen is showing. Dead pixels are caused by manufacturing defects or physical damage to the LCD transistor and generally cannot be fixed with software.

What is a stuck pixel?
A stuck pixel displays one color continuously — typically red, green, or blue — instead of changing with the screen content. Unlike dead pixels, stuck pixels can sometimes be fixed because the transistor is partially functional rather than completely dead.

What is a hot pixel?
A hot pixel appears as a bright white dot that stays lit regardless of the display content. Hot pixels are more common on camera sensors than monitors but can occur on LCD panels where all three sub-pixels are stuck in the on position simultaneously.

Does the stuck pixel fixer actually work?
It works in some cases. Rapidly cycling colors can help a stuck transistor reset itself. Newer stuck pixels that appeared recently respond better than long-standing defects. Running the fixer for five to ten minutes on the affected area gives the best chance of recovery.

How do I know if I have a warranty claim for dead pixels?
Most monitor manufacturers follow ISO 13406-2 standards, which classify acceptable defect levels by panel class. One dead pixel may not qualify for warranty replacement under Class II panels. Check your monitor's documentation or the manufacturer's warranty terms for their specific pixel defect policy.

Does this tool work on mobile?
Yes. The test works on smartphones and tablets using the browser's fullscreen API. However, individual pixels are more difficult to spot on high-density mobile screens — the test is most useful on desktop and laptop monitors.

Which colors are best for spotting dead pixels?
Black is the best color for finding dead pixels because any lit pixel will show against the dark background. White reveals stuck-off pixels and overall backlight uniformity. Red, green, and blue individually expose single-color stuck pixels most clearly.

Do I need to download anything?
No. The tool runs entirely in your browser using the Fullscreen API. Nothing is downloaded, installed, or transmitted. It works on Chrome, Firefox, Edge, Safari, and Opera.

Background

Check your monitor for dead, stuck, or hot pixels with this free online screen test. Fill your entire display with solid colors — black, white, red, green, blue, and grey — to spot any pixel that fails to display correctly against a uniform background.

A dead pixel stays black regardless of what color the screen shows and is typically caused by a permanently damaged transistor. A stuck pixel shows one color continuously — often red, green, or blue — regardless of the content behind it. Stuck pixels can sometimes be revived by rapidly cycling the color signal.

If you find a stuck pixel, activate the built-in stuck pixel fixer, which flashes colors rapidly in a targeted area. Running it for five to ten minutes has the best chance of resetting the transistor. Everything runs entirely in your browser using the Fullscreen API — no downloads, installs, or data collection required.

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