Dead & Stuck Pixel Test.
Click the screen to go full screen, then check each colour edge to edge for pixels that never light up or stay stuck.
How to test your screen
- 1Go full screen
Start the test and let the colour fill the whole display, edge to edge.
- 2Inspect each colour
Cycle through white, black, red, green and blue. Move close and scan the whole panel.
- 3Mark any odd dots
A spot that stays black (dead) or frozen on a colour (stuck) is a pixel defect.
- 4Check the edges
On black, watch for glowing patches — that is backlight bleed, common on IPS panels.
What your results mean
Run the test full screen and inspect each colour up close, then match what you see against the table below — it maps every common pattern to what is actually happening and the next step to take.
| What you see | What it means | What to do |
|---|---|---|
| Every solid colour fills the screen evenly, and up close you cannot find a single dot that misbehaves | A clean panel — no dead, stuck or lit subpixels | Nothing to do. |
| A dot stays black on white and on every colour | A dead pixel — no signal is reaching it | Usually permanent. Rule out dust first, then return a new panel while it is in warranty — see the dead vs stuck pixel guide. |
| A dot is frozen on one colour (red, green, blue, cyan…) while the rest of the screen changes | A stuck pixel — one subpixel is jammed on | Often fixable: leave a colour-cycling test running over it or gently massage the spot, then retest. Steps in the fix guide. |
| A dot is black on one pure colour but looks normal on the others | A single dead subpixel, not a whole dead pixel | Pin the exact channel with the RGB channel test; it is minor and often invisible at normal distance. |
| Glowing patches or a coloured haze near the corners or edges on a fully black screen | Backlight bleed or IPS glow — a lighting issue, not a pixel fault | Gauge how severe it is on the uniformity test; a little is normal, a lot on a new panel is returnable. |
| A speck or smudge that shifts or wipes away when you clean the glass | Surface dust or a mark — not a defect at all | Clean the screen and retest. A real fault sits inside the glass and will not move. |
Dead vs. stuck pixels
Dead pixel
No power reaches it, so it stays black on every colour. Usually permanent — but always confirm with this test before a warranty claim.
Stuck pixel
Frozen on one colour. Often fixable by rapidly cycling colours or gently massaging the spot — retest after a few minutes.
Works on every screen
Monitor
Check a new or used desktop monitor before the return window closes.
Laptop
Inspect a laptop panel for pixel defects and backlight bleed.
Phone & tablet
Tap through solid colours to test a mobile display edge to edge.
TV
Use your remote’s arrow keys to run the test on a smart TV.
Why use Full Screen Test
100% private
Every test runs in your browser. Nothing is uploaded, no sign-up, no account.
Instant & free
No install, no download. Open a test and it works immediately, on any device.
Any screen
Phones, tablets, laptops, external monitors and TVs — anything with a browser.
Frequently asked questions
How do I test my monitor for dead pixels?
Click "Dead & Stuck Pixel Test", enter full screen, and cycle through the solid colours. A dead pixel stays black on every colour; a stuck pixel stays fixed on one colour when the rest of the screen changes. Inspect white and black especially carefully.
What is the difference between a dead and a stuck pixel?
A dead pixel gets no power and stays black on all colours — usually permanent. A stuck pixel is powered but frozen on one colour; it can often be revived by rapidly cycling colours or gently massaging the spot, so retest after a few minutes.
Does this work on a phone, tablet or TV?
Yes. The test fills any screen with a browser. On mobile, tap to advance through the colours; on a TV, use the remote’s arrow keys to switch and the back button to exit.
Is anything uploaded or installed?
No. Everything runs locally in your browser — nothing to install, no sign-up, and none of your activity is uploaded.