A dark dot
A point that stays dark on bright colours may be a non-lighting pixel or subpixel. Surface contamination and physical damage can look similar.
DISPLAY TOOLS / 03
Dead Pixel Test
Take a careful look. Record the dots you notice.
A manual check. Your eyes, your observations.
01 / Pure white#FFFFFF
To leave: press Esc, or tap the screen / press Tab to reveal the return button. If fullscreen is unavailable, browser controls may remain.
YOUR OBSERVATIONS
What did you notice?
Look for dark spots, tint differences or marks on the white field.
Optional. Recorded only in this tab.
The preview and instructions work without JavaScript. Fullscreen, guided results and lighting adjustments require JavaScript; enable it to use those controls.
Step 1 of 5 · White
YOUR RECORD
Your observation summary
These are your selections, not an automated diagnosis.
Up to 1,000 characters. Stays in memory; clears on reload. Never submitted.
No defect is detected or ruled out by this page. If an issue persists, consult the manufacturer’s support or warranty policy. Do not press, rub or flash suspected pixels.
For shading and surface marks, try the broader screen test.
A CLOSER CHECK
Compare the same point on every colour.
This manual dead pixel test displays white, black, red, green and blue. Look for a tiny point that stays in the same physical place as you move through the colours. Record what you see; the page does not detect or count pixels.
- Prepare a clean display using its manufacturer’s care instructions. Do not rub or press a suspected pixel.
- Open white and inspect the display at a comfortable distance. Tap or press Tab to reveal the return button.
- Record any dark, bright or coloured dot, then compare its location on the remaining colours.
Dark, bright or colour-specific?
A bright dot
A point that remains bright against black may be a constantly lit pixel or subpixel. Reflections can also appear bright; compare its location carefully.
A coloured dot
A dot that changes visibility between red, green and blue may involve one colour channel. A website cannot determine its physical cause.
Dot illustrations show the idea only. They are not photographs or size references for real defects.
A dot, a surface mark or a larger patch?
| What you notice | Safe comparison | Limit and next step |
|---|---|---|
| A tiny fixed dot | Compare the same physical location on white, black, red, green and blue. Note which fields make it visible. | Pixel or subpixel behaviour is one possibility; a browser cannot confirm the physical cause. If it persists, contact the manufacturer with your observations and exact model. |
| A mark that might be dust | Turn the screen off and check its surface without pressure. Follow the exact model’s care instructions before cleaning, then recheck. | Dust, coating marks and pixel behaviour cannot always be separated remotely. Do not rub or press a suspected defect. |
| An area or patch | Use the screen test for broader shading; compare at your usual viewing angle and in ordinary content. | A patch is not a pixel count. Reflections and panel behaviour can affect its appearance; persistent changes need manufacturer advice. |
| A mark in a screenshot | Remember that a screenshot records the browser image, not light from the physical panel. | A screenshot is not proof of a defective panel. Keep location notes; ask support what evidence they need. |
No physical defect photographs are presented here. The small dot illustrations are schematics only; they cannot establish what is happening on your display.
If a dot persists
Note which backgrounds make it visible and where it appears. Compare the same place in ordinary content. If it remains concerning, check the manufacturer’s warranty, return terms and support instructions for your exact display.
Pixel policies and panel types differ. This test does not apply a universal acceptable-defect threshold. Avoid pressure, rubbing, disassembly or flashing “fixes.”
Looking beyond individual dots?
The guided screen test adds grey and broader observations for shading, banding and surface marks. The plain white screen is available if you just need an uninterrupted white field.
Does a clear result prove the display is perfect?
No. The summary is a record of what you selected, not an automated pass or fail. Pixel density, eyesight, room lighting, colour management and viewing distance can hide small anomalies.
How this tool works
The display uses exact CSS colour values, rendered locally in your browser. No camera, automatic hardware analysis or observation upload is used. Privacy information is below.
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