Dead Pixel Test
Identify permanently inactive or dark subpixels across your entire display with pure high-contrast color fields.
Diagnostic Sequence Preview
This test automatically cycles through calibrated solid color surfaces.
What to Look For
A dead pixel occurs when the subpixel transistor fails to receive electric current, causing it to remain permanently dark or black. On high-resolution displays (like 4K monitors or Retina screens), a dead subpixel looks like a microscopic black speck.
- Permanent dark or black spots visible against bright backgrounds like white, yellow, or cyan.
- Tiny non-illuminated subpixel specks that do not disappear when cleaned.
- Dark clusters where multiple adjacent pixels have failed.
- Edge vignetting or corners with non-responsive subpixels.
Display Preparation Tips
- 1Clean your screen thoroughly with a microfiber cloth to prevent confusing surface dust with dead pixels.
- 2Increase screen brightness to 100% to maximize subpixel illumination contrast.
- 3Turn off Night Shift, Night Light, and True Tone.
- 4Trigger fullscreen mode to hide browser bars and status tabs.
Frequently Asked Questions
What causes a dead pixel?
Dead pixels are typically caused by manufacturing flaws in the thin-film transistor (TFT) layer, physical impact, or transistor burnout over extended operation.
Can a dead pixel spread?
A single dead pixel does not spread on its own. However, physical pressure or panel damage can cause surrounding transistors to fail over time.
Does warranty cover dead pixels?
Under ISO 9241-307 Class II guidelines, most manufacturers require at least 2 to 5 dead pixels before approving a replacement.
Ready to Check Your Screen?
Launch full-screen diagnostics right now to verify pixel health, backlight uniformity, and color fidelity across your entire display.
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