Comment utiliser : Dead Pixel Test
- Clean the screen, then click Start full-screen test.
- Look closely at each solid color: a black dot on white is a dead pixel; a bright red, green or blue dot on black is a stuck pixel.
- Step through the gradient and grid patterns to check for banding, uneven brightness and backlight bleed, then press Esc.
Dead pixels vs stuck pixels
A dead pixel stays black whatever is shown — easiest to see on the white, red, green and blue screens. A stuck pixel is lit permanently in one color (often red, green or blue) and stands out on the black screen. Stuck pixels sometimes recover after hours of normal use or gentle pressure with a soft cloth while the screen is off; dead pixels rarely do.
Backlight bleed and uniformity
On the black screen in a dark room, LCD monitors may glow at the edges or corners — backlight bleed. Some glow (IPS glow) is normal and changes with viewing angle; bright patches that stay put are bleed. The gray screens reveal uniformity problems such as darker corners or a dirty-screen effect, and the gradients show banding — visible steps where a smooth ramp should be.
Check before the return window closes
Most manufacturers accept a few dead pixels under their pixel policy (ISO 9241-307 classes), so test a new monitor, laptop or TV right away and keep a photo of any defect. The refresh-rate estimate helps confirm that a 120 Hz or 144 Hz display is really running at its full rate — if it shows 60 Hz, change it in your system display settings.
Aussi recherché comme : stuck pixel test, monitor test, screen test, dead pixel checker, backlight bleed test, screen color test, refresh rate test.
Outils complémentaires : Dead Pixel Test
- Test de la webcam — Vérifiez que votre caméra fonctionne correctement et que l'image est de bonne qualité avant un appel vidéo : visualisez l'image en direct, vérifiez la résolution et la fréquence d'images réelles, puis enregistrez une capture d'écran.
- Testeur de clavier — Appuyez sur chaque touche et observez-la s'allumer sur le clavier à l'écran : identifiez les touches défectueuses, bloquées ou qui s'activent en boucle, visualisez la touche et le code correspondant à chaque pression, et vérifiez combien de touches sont détectées simultanément.
- Test de vitesse de clic (CPS) — À quelle vitesse pouvez-vous cliquer ?
- What Is My Screen Resolution — Your screen and browser window sizes in CSS pixels, the device pixel ratio and the real physical resolution — measured live by your browser.