Screen Test & Color Check
Inspect your display using solid colors, grayscale and RGB gradients, gray steps, checkerboards and line patterns. Change patterns manually and optionally open the test field in fullscreen.
1. Choose a test field
View solid white, black, red, green and blue at a comfortable brightness. Look for persistent spots or uneven areas across several colors. Use gradients/steps to inspect visible banding; use fine lines/checkers to compare browser scaling.
2. Inspect the preview
Focus the test field: Left/Right arrows change patterns; Space hides/shows the overlay. Hide overlay leaves one return button; move it to the other corner to inspect pixels underneath. Escape exits fullscreen using your browser's normal controls.
How to interpret what you see
A persistent differently colored spot can be easier to notice on contrasting solid fields, but a browser test does not diagnose or repair hardware. Dust, reflections, viewing angle, panel technology, brightness and image processing can affect appearance. This tool is not color calibration or a color-accuracy measurement.
Patterns are generated in CSS pixels. Browser zoom, device pixel ratio and display scaling affect fine lines/checkerboards; a CSS pixel does not always match one physical panel pixel. Screen and viewport values below come from browser APIs and may not be the panel's native resolution. Fullscreen availability depends on your browser and its permissions.
All patterns are local CSS. No camera, screenshots, processing uploads or saved test history are used. Choose colors and pattern changes yourself; there is no timed cycling or automatic flashing. Website ads and analytics follow the privacy information.
Using Screen Test & Color Check
Use local visual patterns to inspect a display, with manual navigation and no automatic flashing.
- Choose solid colors or a gradient/checker/line pattern. Adjust checker tile size or pick a custom solid color.
- Inspect the preview or choose fullscreen if your browser permits. Hide overlay and move its return button to inspect covered corners.
- Use Left/Right arrows when the field has focus. Space toggles overlay; Escape uses the browser exit from fullscreen.
Example
Compare a persistent spot against white, black, red, green and blue fields. Switch between grayscale gradient, gray steps and fine line patterns to inspect banding and scaling visually.
Questions & answers
Can this diagnose or repair a dead pixel?
No. It provides visual fields that can help you notice persistent spots or uneven areas. A browser test does not diagnose hardware or repair pixels. Dust, reflections, brightness and viewing angle can also affect what you see.
Does it flash colors automatically?
No. Every change is manual. There is no timed cycling or automatic flashing. Use only the patterns and brightness you are comfortable viewing.
How do fullscreen controls work?
Open fullscreen is triggered only by your click. Availability depends on browser support and permission. The button changes to Exit fullscreen; Escape uses normal browser exit controls. If fullscreen cannot open, use the preview or maximize your browser window.
Can I inspect pixels behind controls?
Hide overlay removes the top controls and leaves one return button. Move return button switches its corner; use the other position to inspect pixels that were covered.
What do checker/line patterns measure?
They are visual CSS-pixel patterns, not a calibrated sharpness or native-panel measurement. Zoom, device pixel ratio and display scaling affect how they map to physical pixels.
Are screen dimensions native hardware dimensions?
No guarantee. Viewport and screen dimensions come from browser APIs in CSS pixels. Device pixel ratio may also reflect zoom/scaling. The tool does not query the monitor hardware.
Is this color calibration?
No. Solid colors and gradients are visual checks. Color accuracy requires an appropriate calibration/measurement workflow; this tool does not measure gamma, gamut or brightness.
What are the keyboard controls?
Focus the test field. Left/Right arrows choose the previous/next preset; Space hides or shows the overlay. Buttons also work normally with the keyboard. Escape is handled by the browser for fullscreen exit.
Are screenshots or display data uploaded?
No screenshots or processing uploads are used. Patterns render locally in CSS and the tool keeps no saved test history. Website ads and analytics follow the privacy information.
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