Monitor color test
Check your screen's color and uniformity in seconds. Cycle through solid red, green and blue swatches, smooth gradients that reveal banding, and grayscale steps for contrast — all rendered locally in your browser with nothing uploaded.
Inspect color reproduction and panel uniformity. Pick a test pattern, then use fullscreen to check edge-to-edge. In fullscreen, use the arrow keys to cycle patterns and Escape to exit.
Test pattern
100% local — nothing leaves your device
How to use it
- 1 Click a solid color swatch and look for dust, dead pixels or backlight unevenness.
- 2 Open the gradient view and scan for visible bands or stripes instead of a smooth blend.
- 3 Switch to the grayscale steps to confirm you can tell every shade apart.
- 4 Press fullscreen for an edge-to-edge view, then press Esc to exit.
Troubleshooting
Color test shows banding or stripes in the gradient
Visible bands usually mean the display or graphics output is limited to 6-bit or a low color depth. Set your monitor to its native resolution, raise color depth to 8-bit or higher in your OS display settings, and disable any "limited RGB range" option on HDMI to restore a smooth gradient.
Colors look washed out or wrong on Windows 11
Open Settings, System, Display and check that the correct ICC color profile and full RGB range are selected. Disable HDR if your monitor is SDR-only, run the built-in display calibration, and update your graphics driver. A wrong profile or limited range is the most common cause of dull, inaccurate color.
Fullscreen color test not working in Chrome or Safari
Fullscreen needs a user gesture, so click the fullscreen button directly rather than triggering it from a script. If nothing happens, exit any existing fullscreen with Esc first, check the browser is up to date, and confirm the site is not blocked from fullscreen in your browser's site settings.
Screen color looks uneven or tinted near the edges
Display a solid white or gray swatch in fullscreen and view it straight on in a dim room. Patches that are brighter, darker or tinted reveal backlight bleed or panel non-uniformity. Lower the brightness, and if the tint shifts as you move your head it is normal viewing-angle behavior, not a fault.
Frequently asked questions
Is anything uploaded or recorded by this color test?
No. The test only fills your browser window with colors and gradients drawn locally. It needs no camera, no microphone and no permission, and nothing about your screen is ever sent to a server.
What is a color banding test and what does it show?
A banding test displays a smooth gradient that should blend seamlessly from one color to another. If you see distinct steps or stripes instead, your display or graphics pipeline cannot reproduce enough shades, often a sign of 6-bit panels or a limited color range.
Can this check my monitor's color accuracy?
It helps you spot obvious problems like banding, dead pixels, tints and uneven backlight by eye. For precise, measured color accuracy you still need a hardware colorimeter, but this test is a fast, free first check before calibration.
How do I fix color banding I find with this test?
Set your monitor to its native resolution, raise color depth to 8-bit or higher in your OS display settings, switch HDMI output from limited to full RGB range, and update your graphics driver.
Does the screen color test work on phones and tablets?
Yes. It runs in any modern mobile browser such as Chrome and Safari. Turn off auto-brightness and any blue-light or night mode first so the colors you see are not being altered by the device.
Which browsers are supported?
Any modern browser works, including Chrome, Edge, Firefox, Safari and Opera on desktop and mobile, since the test only uses standard HTML, CSS and the Fullscreen API.