Screen & Dead Pixel Test
Test your display panel directly on this page or in true full screen. Inspect RGB color purity, panel uniformity, backlight bleed, and spot defective dead or stuck subpixels across 9 calibrated color backdrops.
1. Pure White (#ffffff)
Check dead pixels (unlit black dots) & backlight purity
Ready to Test Your Screen & Dead Pixels
Begin the guided solid color sweep to verify edge-to-edge chromatic purity, detect black dead subpixels, spot stuck glowing color specks, and inspect backlight bleed halos.
Understanding Display Defects: Dead vs. Stuck vs. Hot Pixels
Modern screens (OLED, IPS, VA, TN) assemble pictures from millions of microscopic RGB (Red, Green, Blue) subpixel triads. Understanding which transistor state failed tells you whether the defect can be repaired.
Dead Pixel
A dead pixel occurs when one or all three subpixel thin-film transistors (TFTs) are permanently unpowered in the OFF position.
Appears as an unlit black dot against bright or pure white backgrounds. Visible on all RGB screens.
Software fixers cannot revive dead pixels. Requires manufacturer panel replacement.
Stuck Pixel
A stuck pixel occurs when a liquid crystal cell or transistor locks in the ON position for a single subpixel channel (Red, Green, or Blue).
Appears as an intensely glowing colored dot (bright Red, Green, or Blue) against a solid Black screen.
High success rate using high-speed chromatic flashing with our Stuck Pixel Fixer.
Hot Pixel
A hot pixel happens when all three subpixels (R+G+B) receive uninterrupted voltage and lock ON simultaneously at maximum output.
Appears as a glowing white pinpoint against pure Black and dark scenes, unaffected by image color.
Occasionally resets after prolonged power cycling, but usually requires hardware service.
๐ก Backlight Bleeding vs. IPS Glow
When inspecting the Pure Black screen in a dark room, many users mistake normal optical panel glow for defective hardware leakage. Here is how to diagnose them:
- Backlight Bleeding (Hardware Assembly Defect):Caused by physical pressure on the LCD frame or pinched bezel corners, allowing raw edge LED light to leak through. Bleed remains visible in the exact same spot regardless of your viewing angle or distance.
- IPS Glow (Normal Panel Characteristic):In-Plane Switching crystals reflect ambient light differently at extreme angles. When you move your head or shift perspective, the corner glow shifts or disappears. This is an optical trait, not a defect.
๐ซ๏ธ Dirty Screen Effect (DSE) & Grayscale Uniformity
The 50% Gray (#808080) test field exposes luminance non-uniformity across the panel diffuser sheets that solid white or black screens can easily conceal:
- Dirty Screen Effect (DSE):Cloudy, smudgy, or shadowy patches noticeable when scrolling or during panning shots in games and sports. It stems from uneven backlight bonding or diffuser film inconsistencies.
- Edge Vignetting & Color Banding:Check whether the screen corners dim excessively compared to the center (vignetting), and confirm that gradients between RGB subpixels remain continuous without stepped color banding.
ISO 9241-307 Display Defect Standards & Return Policy
Manufacturers classify display warranty claims according to the international ISO 9241-307 standard (defects per 1,000,000 pixels):
| ISO Class | Dead Pixels (Black) | Hot Pixels (White) | Stuck Subpixels (RGB) | Common Device Categories |
|---|---|---|---|---|
| Class 0 | 0 | 0 | 0 | Medical imaging displays, military avionics, master color-grading monitors. |
| Class 1 | โค 1 | โค 1 | โค 2 | High-end flagship monitors, professional creator laptops (e.g. Apple Pro Display XDR). |
| Class 2 (Standard) | โค 2 | โค 2 | โค 5 | 95% of consumer monitors, gaming laptops, and workstation displays. |
| Class 3 / 4 | โค 5+ | โค 15+ | โค 50+ | Ultra-budget panels, industrial POS terminals, automotive dash screens. |
Tip for New Purchases: Most retailers offer a 14โ30 day no-questions-asked return window. Always perform this test immediately upon unboxing so you can request an exchange before manufacturer warranty clauses apply.
Run Stuck Pixel Fixer & Noise Generator โ
Found a glowing red, green, or blue dot? Exercise the frozen liquid crystals with high-speed chromatic flashing in an interactive resizable window.
Complete 60s Full Device Audit โ
Certify your entire computer including speakers, microphone, keyboard ghosting, webcam & camera, and mouse polling alongside your screen results.