Dead Pixel Test for iPhone, Samsung, laptop, and monitor screens
Check your monitor for dead, stuck, or hot pixels using 8 full-screen color panels — no software required.
💡 How do I check for dead pixels?
Click Start Fullscreen Test to run a dead pixel test on an iPhone, Samsung, laptop, monitor, or tablet screen. Your screen will fill with a solid color — scan slowly for any dots that don't match the background color. Click or press the arrow keys to cycle through black, white, red, green, blue, cyan, magenta, and gray. Dead pixels appear black on every color. Stuck pixels hold one color regardless of the background. Hot pixels glow bright white on dark screens.
Dead, stuck, or hot — what's the difference?
Dead pixel
A pixel that receives no power and stays permanently black. Dead pixels are easiest to spot on white or bright color screens. They cannot be fixed with software.
Stuck pixel
A pixel stuck showing one color (often red, green, or blue) regardless of what's on screen. Stuck pixels are sometimes fixable by running pixel-cycling software or applying gentle pressure.
Hot pixel
A pixel that is always on, appearing bright white on dark screens. Hot pixels are a common form of stuck pixel and are most visible on black backgrounds.
Can dead pixels be fixed?
Truly dead pixels (no power) typically cannot be fixed. Stuck pixels sometimes respond to pixel-exercise tools that rapidly cycle colors to 'unstick' the transistor. Gentle pressure with a soft cloth on the affected area can occasionally help. If your monitor is under warranty, most manufacturers consider 3–5 or more dead pixels a defect eligible for replacement — check your monitor's warranty terms.
Frequently asked questions
- How many dead pixels is acceptable?
- Industry standards vary. ISO 13406-2 defines defect classes: Class I allows zero defects, Class II allows up to 2 fully dead pixels. Most consumer monitor warranties cover replacement only above a threshold of 5–8 dead pixels depending on the brand. Check your monitor's manual for the exact policy.
- Should I test a brand new monitor?
- Yes — do it within your return window (usually 14–30 days). Dead pixels are sometimes present from the factory, and catching them early makes warranty claims much easier. Test all 8 color panels on a new monitor.
- Can I fix a stuck pixel myself?
- Sometimes. Pixel-cycling tools that rapidly switch colors can occasionally unstick a stuck pixel by warming the liquid crystal. Gently massaging the pixel area with a soft cloth while cycling colors is another common technique. Results vary — dead pixels (permanently off) cannot be fixed this way.
- Does this test work on laptops?
- Yes — the test works on any screen including laptops, external monitors, and TVs. For laptops, make sure the browser is in full-screen mode (F11) to cover the entire panel area.
- Can I use this test on my TV?
- Yes. Open this page in a browser on a device connected to your TV, enter fullscreen, and cycle through the colors. The test works on any display that can show a web browser.
