This tool cycles through 5 solid colours. Look across the entire screen for any pixel that does not match the current colour — that is a dead or stuck pixel.
WhiteBlack dot indicates dead pixel
BlackBright dot indicates stuck pixel
Red / Green / BlueWrong-colour dot indicates stuck pixel
Click anywhere or use arrow keys to advance. Press F for fullscreen.
Flashing lights warning
The fixer flashes bright colours rapidly inside a small box. Do not use it if you have photosensitive epilepsy or are sensitive to flashing lights, and stop at once if you feel unwell.
Drag the box (or use the arrow keys) over the stuck pixel and leave it flashing — up to 10 minutes can help. Press Esc to stop.
Select Manual Test or Auto-Cycle to begin. Advance through each colour by clicking the screen or pressing the arrow keys. For best results, go fullscreen and dim the room lights.
What is a dead pixel?
A dead pixel is permanently off — it shows as a black dot regardless of what is on screen. Dead pixels cannot be fixed and typically indicate a hardware defect.
What is a stuck pixel?
A stuck pixel is permanently on in one colour — red, green, or blue. Unlike dead pixels, stuck pixels can sometimes be resolved with pixel-cycling software or gentle pressure.
When to check?
Run this test on any new monitor, laptop, or TV immediately after purchase, while you are still within the return window.
How many is acceptable?
ISO 13406-2 defines defect classes. Most consumer monitors allow up to 2 dead pixels before qualifying for a warranty replacement — check your manufacturer's policy.
Stuck pixel fixer
A stuck pixel is sometimes just a stuck sub-pixel. The fixer flashes colours rapidly in a small box you place over it — it can help, but dead pixels and hardware faults won't respond.
FAQ
Manual mode lets you step through each test colour at your own pace with the arrow keys; Auto-Cycle advances automatically, which is useful when you're checking a screen from a distance or recording the process.
No — it only displays solid colours, the same as any webpage. It can't cause or worsen pixel defects.
Sometimes. Try running Auto-Cycle for a few minutes, or gently massaging the area with a soft cloth while the pixel is cycling colours. Dead pixels, unlike stuck ones, generally cannot be fixed.
Sometimes. It cycles the pixel through colours very quickly, which can free a pixel that is only temporarily stuck on. It can't repair a dead pixel or physical damage, and results vary — if nothing changes after about 10 minutes, check your warranty.
The box is small, but rapid flashing can trigger seizures in people with photosensitive epilepsy and cause discomfort for others. You must confirm a warning before it starts, and Esc or Stop ends it immediately.