How to check for dead pixels
Press "Start full-screen test" to fill the screen with one color. Click or press Space to go to the next color (ESC to exit).
- A bright dot on a black screen → hot pixel (always on)
- A black dot on a white screen → dead pixel (always off)
- A differently colored dot on red, green or blue → subpixel defect
- Bright bleeding at the edges on a black screen → backlight bleed (IPS glow)
When should I check?
When you get a new monitor, laptop or secondhand device, check right away within the exchange or return period. Manufacturers' zero-defect policies (how many dead pixels qualify for an exchange) differ, so check the seller's policy too.