Dead Pixel Test — Full-Screen Colour Checker
Solid colours, full screen, nowhere for a faulty pixel to hide. Click through black, white, red, green, blue and more, and inspect your panel one colour at a time.
Inside fullscreen: click or press the right arrow for the next colour, left arrow to go back, Esc to exit.
How to run the dead pixel test
- Clean the screen first with a dry microfibre cloth — dust is the great dead-pixel impersonator.
- Start the fullscreen test and dim the room lights; faults are far easier to spot without reflections.
- On each colour, scan slowly in a grid pattern, corner to corner. Take your time on black and white — they carry most faults.
- Mark anything suspicious and check it on the next colours: a spot that stays black through every colour is dead; a spot glowing one colour on black is stuck.
- Photograph genuine faults with the colour and position noted — useful evidence for a warranty or return claim.
Dead, stuck and hot: telling faults apart
Each pixel on an LCD or OLED is built from red, green and blue subpixels, and faults live at that level. A dead pixel is dark in every colour — its transistor or emitter has failed outright. A stuck pixel has one subpixel jammed on, so it shines a constant red, green or blue point, most visible on black. A hot pixel is the camera-sensor cousin and rarely applies to monitors. The colour cycle in this test is designed around those definitions: on the matching solid colour a stuck subpixel disappears into the field, while on the opposite colours it stands out — which is how you can name the fault precisely instead of just knowing something is there.
Do the test when a panel is new and again before any return window closes. Manufacturers' pixel policies are written in counts and classes, and a fault that is obvious to you may sit inside the allowed count for a budget panel while being grounds for replacement on a premium one. The photograph and the count are what a support conversation runs on. If your panel is clean but motion looks wrong, the fault is elsewhere: try the ghosting test for trailing, the frame skipping test for missing frames, or the monitor test hub for the whole suite.
Frequently asked questions
What is a dead pixel versus a stuck pixel?
A dead pixel receives no power and stays black on every colour. A stuck pixel is frozen on one colour — it will glow red, green or blue even on a black screen. Cycling solid colours, as this test does, separates the two immediately.
Can a stuck pixel fix itself?
Sometimes. Stuck pixels occasionally recover over hours of normal use, and gentle pressure or rapid colour cycling is widely reported to help some of them — but nothing is guaranteed, and dead pixels are permanent. Check your manufacturer's pixel policy while the panel is under warranty.
Which colour shows which fault?
Black screens reveal stuck bright pixels; white screens reveal dead dark ones; red, green and blue screens isolate faults in each subpixel. That is why the test cycles all of them rather than just black and white.
How many bad pixels are acceptable for a return?
Policies vary by brand and panel class — some allow a handful of subpixel faults, premium lines allow none. Photograph what you find and check the policy for your exact model before the return window closes.
Should I clean the screen first?
Yes. A speck of dust looks exactly like a dead pixel at arm's length. Wipe the panel gently with a microfibre cloth before you start, and ignore anything that moves when you do.