Dead Pixel Test
Find dead, stuck or hot pixels on your monitor, laptop screen or TV. Pick a solid color (or a smooth gradient), turn on the grid to locate a bad spot precisely, and hit Fullscreen to test your entire display — all in your browser, nothing uploaded.
What is a dead pixel?
A dead pixel is a single point on your display that no longer responds — it stays dark (or stuck in one color) no matter what you show. They usually appear as a tiny dot near the edge of the panel and are caused by a failed transistor or sub-pixel driver. Because they're easy to miss, testing against several solid backgrounds is the most reliable way to catch them.
Dead vs stuck vs hot pixels
- Dead pixel — never lights up; it looks black on every color you test.
- Stuck pixel — permanently lit in one color (red, green or blue) regardless of the image. It often shows only against a contrasting background, so cycle through all the colors above.
- Hot pixel — a stuck sub-pixel that glows brighter than its neighbors, most visible on dark backgrounds like black.
How to use this dead pixel test
Pick a solid color and scan the whole panel slowly, moving your head slightly to catch faint defects. Start with red, green, blue, white and black — that combination exposes almost every defect type. Turn on the Grid overlay (and shrink the cell size) to pinpoint exactly where a bad pixel sits so you can report it or track it over time. Use the gradients to check for banding and uneven backlight, then hit Fullscreen to cover your entire screen including areas hidden behind browser chrome.
Can you fix a dead pixel?
Sometimes. Stuck pixels can occasionally be freed by displaying the opposite color on that spot for an extended period (a "pixel-fixing" video does this). True dead pixels are hardware damage and usually can't be repaired, but many manufacturers will replace a panel if it has more defective pixels than their stated threshold — so use the grid to count them.
Frequently asked questions
Does this work on phones and tablets? Yes — tap Fullscreen (or your device's own fullscreen) and test each color. On touch screens you can also drag a finger across the panel to check for pressure-sensitive defects.
Why do I need several colors instead of just one? A dead pixel is invisible on black, and a red stuck pixel is invisible on red. Testing all the primary colors plus white and black guarantees nothing hides.
Is anything uploaded from my screen? No — the test is drawn entirely by your browser's own renderer; no screenshot or data leaves your device.