Visual Regression & Image Diff Checker
Images & design Local only
Screen Dead Pixel & Uniformity Test
Private manual display testInspect dead, bright or stuck pixels and screen uniformity with local full-screen color patterns.
Visual inspection—not automatic diagnosis or repair
Use a comfortable brightness and short sessions. This page does not detect physical pixels automatically, does not rapidly flash colors, and cannot decide a warranty claim. Avoid leaving bright static patterns on OLED displays.
Pattern 1 of 11: Black
Keyboard: ←/→ colors · M mark · H markers · C controls · Esc exit. Swipe horizontally on touch screens.
How to use it
- 01
Prepare the display
Clean the panel gently, let it warm up, choose a comfortable brightness and use the native display resolution.
- 02
Inspect full-screen patterns
Cycle black, white, primary colors, dark steps, bright steps and grayscale while scanning the panel from several viewing positions.
- 03
Record only what you observe
Mark suspect locations, distinguish repeatable pixel behavior from surface dust, then export a local report for follow-up.
Frequently asked questions
Can a web page automatically detect a dead pixel?
Not reliably. A page cannot directly sense the light emitted by each physical pixel, so this tool presents controlled patterns and records your observations.
What is the difference between a dead, bright and stuck pixel?
A dead pixel usually stays dark, a bright pixel remains lit on dark patterns, and a stuck pixel can remain on one color channel. Panel technology can change the appearance.
Why should I test in full screen?
Full screen removes most browser chrome and exposes more of the panel to one exact color, making small persistent points easier to spot.
Does this tool repair or flash stuck pixels?
No. It deliberately avoids rapid flashing and makes no repair claim. Follow the display maker's support guidance before attempting any treatment.
Is the test safe for OLED displays?
Use moderate brightness and short sessions, especially for OLED. Do not leave high-brightness static patterns on screen longer than needed.
Why are dark and bright step patterns included?
Near-black and near-white levels can reveal pixels or uniformity differences that are less visible on absolute black or white.
Can dust look like a bad pixel?
Yes. Clean only with the manufacturer's recommended method, change viewing angle and retest the same coordinate on several colors before classifying it.
Does browser zoom affect the result?
The solid color still covers the stage, but native resolution and normal zoom make grid positions and repeat tests easier to compare.
What does the report prove?
It documents a manual visual inspection, its display environment and marked coordinates. It is not a calibrated measurement or warranty determination.
Are screenshots or screen contents uploaded?
No. The test draws CSS colors locally, requests no screen capture, and builds reports inside the browser.
Can I use the tool on a phone or tablet?
Yes. Touch navigation and full screen work where the browser exposes the Fullscreen API, though browser controls may remain visible on some mobile systems.
How long should a test take?
A careful pass through the quick colors often takes a few minutes. Pause when your eyes feel tired and repeat suspicious locations rather than staring continuously.
Related tools
Keep working with other focused browser utilities.