Infinite Dead Pixel Tester
Cycle through high-intensity solid colors to spot stuck or defective hardware pixels.
Instructions: Once the test starts, tap or click to cycle colors. Look closely for any dot that remains a different color.
What are Dead and Stuck Pixels?
Your screen is made of millions of tiny "sub-pixels" (Red, Green, Blue). A dead pixel is one that has lost power entirely and appears as a permanent black dot. A stuck pixel is one where one or more sub-pixels are permanently "on," appearing as a bright red, green, or blue dot. Our online dead pixel tester helps you identify these defects by cycling your display through contrasting colors in full-screen mode.
How to Test for Display Defects
The most reliable way to find a pixel defect is to use a high-fidelity solid background. On a white background, you can easily spot dead (black) pixels. On a black background, you'll see stuck (bright) pixels. Our online screen checker automates this process. By using our professional monitor tester, you can perform a complete audit of your panel's health—essential after buying a new laptop or monitor.
Can You Fix a Stuck Pixel?
While a "dead" pixel is usually a physical hardware failure, a "stuck" pixel can sometimes be revived. Our pixel fixer tool uses rapid color flashing to "exercise" the liquid crystals in the panel. While not guaranteed, running our online pixel repair mode for 10-20 minutes can sometimes unstuck a sub-pixel and return your panel to perfect condition.
Privacy and Panel Health Safety
At 99tool.in, your safety is our priority. Our private pixel test runs entirely locally in your browser. We do not record your results or hardware specs. We recommend using our secure display checker in a darkened room for the best results. Our tool is safe for all LCD, OLED, and LED panels, providing the high-fidelty diagnostic you need without installing intrusive software.