Dead pixels, colours and refresh rate of your screen
Free screen test: dead or stuck pixels in full screen, uniformity and backlight bleed, gradients, real refresh rate (60, 120, 144 Hz…) and display specs.
Dead pixels and colours
In full screen: click or → for the next colour, ← to go back, Esc to exit. Look for a dot that does not change colour.
⚠ Rapid flashing is not advised for people sensitive to photosensitive epilepsy.
Refresh rate
Measuring, keep the window still…
The square should glide without stutter or trails.
Your display
FAQ
What is the difference between a dead and a stuck pixel?
A dead pixel stays black on every colour: it is permanently off. A stuck pixel stays lit in one colour (red, green, blue or white); it can sometimes be fixed with gentle pressure or rapidly flashing colours.
Why does it show 60 Hz on a 144 Hz monitor?
The monitor is probably set to 60 Hz. Windows: Settings › Display › Advanced display › Refresh rate. Mac: Settings › Displays. Also check the cable (DisplayPort or HDMI 2.0+) and power-saving mode.
What is backlight bleeding?
Brighter patches on the edges of an LCD screen showing black, caused by backlight leaking out. A slight glow is normal; very visible patches may justify a return.