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Monitor Test Patterns

Diagnose dead pixels, uniformity, overscan, and color banding with a suite of monitor test patterns.

Free to use, no watermarks, runs in your browser—nothing uploads to our servers

View the patterns in a dim room for best results. Inspect corners for color tinting, look for ghosting on the checkerboard while scrolling, and use the grid to align your display’s scaling controls.

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If this tool misbehaves, share a quick summary so we can investigate. We include the tool URL automatically—no need to copy and paste.