Dead pixel test
Solid colours, one at a time. A dot that stays black on every colour is a dead pixel; one stuck on a single colour is a stuck pixel.
TV screen test patterns
Check a TV or monitor for dead pixels, overscan, colour problems and banding. Pick a pattern to fill your screen, or mirror it to the TV first and run the test on the big screen.
Pick a test pattern
Each pattern opens fullscreen. Click or tap to step through, press Esc to exit. On the dead pixel test, any dot that stays the wrong colour on every screen is a stuck or dead pixel.
How to read the patterns
Overscan and edges
If the outer frame and all four corners are visible, the TV is not cropping. If edges are cut off, turn off overscan or set the picture size to Just Scan or Screen Fit.
Colour bars
Standard bars to judge colour and saturation, and to spot a TV that shifts hue or clips bright colours.
Gradient and sharpness
A smooth gradient reveals banding; the fine grid shows whether the panel resolves detail cleanly or looks soft.
Mirror straight from your browser
Try MHL Mirroring on your own screens
Open the receiver on the TV, the sender on your computer, and connect with a 6-digit code. Free, peer-to-peer, nothing to install.
More tools
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