How to Check for Dead Pixels on Any Screen

Whether you've just bought a new monitor or you're noticing annoying spots on your laptop screen, performing a dead pixel check is essential. Dead pixels can be distracting and, in some cases, a sign of manufacturing defects eligible for warranty replacement.

What is a Dead Pixel?

A pixel is "dead" when it fails to light up, appearing as a tiny black dot on your screen. This happens when the transistor driving the pixel fails. Since the pixel blocks the backlight (on LCD/LED screens) or doesn't emit light (on OLED screens), it remains permanently dark.

Contrast this with a stuck pixel, which is frozen in a specific color (usually red, green, or blue). Stuck pixels are often easier to spot and sometimes easier to fix than dead pixels.

How to Check for Dead Pixels

The most reliable way to find dead pixels is to inspect your screen against solid color backgrounds. Here is the step-by-step process:

1. Clean Your Screen: Dust and smudges can look exactly like dead pixels. Wipe your screen gently with a microfiber cloth before starting.
2. Use Fullscreen Colors: You need a tool that fills your entire screen with a single color. Our Dead Pixel Detector does exactly this.
3. Cycle Through Colors:
   • White: Best for checking general dead pixels/dirt.
   • Black: Helps spot stuck pixels (they will shine bright against the dark).
   • Red, Green, Blue: Essential for checking specific sub-pixel failures.
4. Inspect Carefully: Scan your screen grid by grid. Look for any dot that doesn't match the background color.

Checking on Different Devices

Monitors and Laptops

For desktop monitors and laptops, simply use your browser. Press F11 (on Windows) or Control+Command+F (on Mac) to go fullscreen while using our test tool.

Pro Tip: Don't forget to check the edges of the screen, where manufacturing defects often occur.

Mobile Phones (iPhone & Android)

Phone screens have extremely high pixel densities (PPI), making individual pixels hard to see with the naked eye. To check a phone screen:

• Turn your brightness to 100%.
• Use a test tool to display a white background.
• Look closely for any irregularities. Since pixels are so small, a "dead pixel" might actually look like a tiny dim cluster.

What If You Find One?

If you confirm a dead pixel, check your manufacturer's warranty policy immediately. Many brands like Dell, ASUS, and Apple have specific "pixel policies" that dictate how many dead pixels are required for a replacement (e.g., ISO 13406-2 standard).