Blue Screen — Fullscreen Blue Display & Pixel Test Color

Fill your screen with pure blue for dead pixel checks, mood lighting, or a solid blue background. Not an error screen. Free and runs in your browser.

What it does

This page shows a pure blue (#0000ff) screen fullscreen. It’s a standard color for checking a display’s blue channel and looking for stuck or dead pixels, and it also works as a solid background or a cool-toned mood light.

How it works

Pure blue lights only the blue element of each pixel, which makes mismatched or stuck pixels easy to spot. The color is plain CSS, so it displays exactly as your screen can render it. For a softer shade such as navy or sky blue, search the named color list, or drag on the screen to shift the hue and brightness. If you need the color in another format, the color format converter turns hex into rgb or hsl.

How to use it

1. Press Go fullscreen (or F).
2. Scan for dots that don’t match the rest of the screen.
3. Use the dimmer to lower the intensity, or pick a lighter or darker blue.
4. Press Esc to exit.

FAQ

Is this the Windows “blue screen of death”?

No. This is a plain blue color for display testing and decoration. It doesn’t simulate or hide a system error, and it can’t tell you anything about your computer’s stability.

Is blue light bad at night?

Bright blue-rich light in the evening can make it harder to wind down for some people. For night use, a dimmer or warmer color is usually more comfortable.

What does a stuck pixel look like on blue?

It appears as a dot that stays another color, such as red, green or white. The Display test mode in the Color Screen tool lets you check all five test colors in sequence.

Privacy

Everything runs in your browser. Nothing is uploaded and no network requests are made while you use it.