What is the difference between a dead pixel and a stuck pixel?

A dark fault can look black on bright fills, including white. A stuck sub-pixel can show a bright red, green or blue dot on black. Switch between white, black and the primary colours to compare appearances. Dirt or a surface mark may also resemble a fault. The test shows colours for your visual inspection; it cannot prove the electrical cause or count faults automatically.

Can this test fix a dead or stuck pixel?

No repair is performed or verified. Automatic advance changes the displayed fill every three seconds for inspection. It is not a pixel-repair procedure, and cycling colours does not establish that a defect has been repaired.

Is the displayed pixel count my panel’s native resolution?

It is an estimated rendering grid from browser screen size and device pixel ratio. Browser zoom, operating-system scaling and external displays can change that estimate without changing the hardware panel. For native resolution and warranty thresholds, use the manufacturer’s specifications and the terms for your exact model.

Does this work on an iPhone, iPad or Android phone?

Open the page in the device’s browser and tap a fill to advance. On browsers that refuse or lack fullscreen, including some mobile Safari versions, the overlay covers the tab and says so. Pixels behind browser or operating-system bars remain outside that fill. Exit and Escape leave the test, and keyboard controls stay available.

Can I test a 4K, ultrawide, LCD, LED or OLED display?

The solid fills scale to the area the browser can cover, without a fixed image resolution. On a connected monitor or TV, move the browser window to that display and enter fullscreen if supported. A TV needs a usable browser or a connected computer; no video, casting app or USB test image is generated. Browser colour processing and panel behaviour remain outside this visual check.

Are black, white and RGB screen tests included?

All eight includes white, black, red, green, blue, mid-grey, yellow and cyan. Primaries uses red, green and blue. Greys uses white, mid-grey and black. Click a swatch to begin on a specific colour; Space, arrow keys and the on-screen buttons advance or go back. The controls use an opaque panel and fade when idle.

Can I test a camera sensor, a VR headset or an uploaded image?

This page fills a browser display. It does not analyse camera RAW files, sensor dark frames or uploaded photographs, and it does not create an immersive per-eye VR scene. It also does not download an APK, native program, test image or video.

Does anything about my screen leave my browser?

Screen dimensions and pixel ratio stay in the browser and are used only for the displayed estimate. No image is uploaded and no test input is stored. The site’s ordinary privacy-controlled usage metrics contain no screen dimensions, colours, pixel counts or fault observations.

Dead Pixel Test

Display eight solid colour fills and inspect persistent dark or bright dots. Step manually or cycle every three seconds. The controls fade when idle so you can inspect the area beneath them, and return on movement, a tap or a key. When native fullscreen is unavailable, a labelled overlay covers the browser tab.

White: dead pixels show as black dotsClick a colour, or Space / → to step through. Esc leaves full screen.

Colours

Advance

Browser estimate: measuring

The full sweep of eight colours for a visual screen check.

Dead pixelblack on every colour
A dark pixel fault can look black on bright fills, white included. A visual check cannot prove its electrical cause.
Stuck pixelred, green or blue on every colour
A stuck sub-pixel can look red, green or blue even on black. Appearance sometimes changes, but this test does not repair pixels.
Dirt or a markmoves when you clean it
Not a pixel fault: it moves or disappears when the screen is wiped. Try a soft dry cloth before making a claim.

Look, do not squint. Sit at your normal distance and let each colour hold the screen for a few seconds: a fault is easier to see when you are not hunting for it. A persistent dark or bright dot across fills may be a pixel fault. This is a visual check; the page does not detect faults automatically or repair them. The estimated rendering grid above comes from browser screen size and pixel ratio. Zoom, display scaling and external displays can make it differ from the panel’s native resolution. Use the manufacturer’s exact panel specifications and warranty terms for a claim.

Accuracy. The browser draws pure full-screen fills, or a tab overlay when fullscreen is unavailable. Whether a pixel is dead or stuck is your eye's call; the notes say what each looks like.

Common questions

What is the difference between a dead pixel and a stuck pixel?: A dark fault can look black on bright fills, including white. A stuck sub-pixel can show a bright red, green or blue dot on black. Switch between white, black and the primary colours to compare appearances. Dirt or a surface mark may also resemble a fault. The test shows colours for your visual inspection; it cannot prove the electrical cause or count faults automatically.
Can this test fix a dead or stuck pixel?: No repair is performed or verified. Automatic advance changes the displayed fill every three seconds for inspection. It is not a pixel-repair procedure, and cycling colours does not establish that a defect has been repaired.
Is the displayed pixel count my panel’s native resolution?: It is an estimated rendering grid from browser screen size and device pixel ratio. Browser zoom, operating-system scaling and external displays can change that estimate without changing the hardware panel. For native resolution and warranty thresholds, use the manufacturer’s specifications and the terms for your exact model.
Does this work on an iPhone, iPad or Android phone?: Open the page in the device’s browser and tap a fill to advance. On browsers that refuse or lack fullscreen, including some mobile Safari versions, the overlay covers the tab and says so. Pixels behind browser or operating-system bars remain outside that fill. Exit and Escape leave the test, and keyboard controls stay available.
Can I test a 4K, ultrawide, LCD, LED or OLED display?: The solid fills scale to the area the browser can cover, without a fixed image resolution. On a connected monitor or TV, move the browser window to that display and enter fullscreen if supported. A TV needs a usable browser or a connected computer; no video, casting app or USB test image is generated. Browser colour processing and panel behaviour remain outside this visual check.
Are black, white and RGB screen tests included?: All eight includes white, black, red, green, blue, mid-grey, yellow and cyan. Primaries uses red, green and blue. Greys uses white, mid-grey and black. Click a swatch to begin on a specific colour; Space, arrow keys and the on-screen buttons advance or go back. The controls use an opaque panel and fade when idle.
Can I test a camera sensor, a VR headset or an uploaded image?: This page fills a browser display. It does not analyse camera RAW files, sensor dark frames or uploaded photographs, and it does not create an immersive per-eye VR scene. It also does not download an APK, native program, test image or video.
Does anything about my screen leave my browser?: Screen dimensions and pixel ratio stay in the browser and are used only for the displayed estimate. No image is uploaded and no test input is stored. The site’s ordinary privacy-controlled usage metrics contain no screen dimensions, colours, pixel counts or fault observations.

Solid CSS colour fills for visual inspection. The browser and display control their rendering; this page does not detect or repair faults, certify physical panel resolution or decide warranty eligibility.