Blue Screen
Show a standard pure-blue background in one click, enter full screen, and optionally leave automatically after a timer.
Full-screen settings
The timer starts after full screen begins. Unlimited means the page will not exit automatically.
Ready to enter the standard pure-blue full screen.
Controls hide after a few seconds in full screen. Press H to show or hide them; press Esc to exit.
Pure-blue output
- Timer
- Unlimited
- Full-screen state
- Not full screen
- Control state
- Controls visible
The page outputs a numeric color only; it does not change hardware brightness, color mode, or calibration parameters.
Use and interpret
Use and keyboard controls
Choose an exit timer and select Enter blue full screen. In full screen, H shows or hides the controls and F toggles full screen. When the preview is focused, Enter enters full screen and Esc exits using the browser's native control.
Why the output is fixed at #0000FF
The standard numeric blue output is RGB(0,0,255). Page brightness, opacity, or custom colors would change the pixels, so this tool does not provide a color-changing slider. Use the display or system brightness setting if you need a dimmer view and record that condition.
Observation conditions and recording
For blue-channel or pixel observation, fix the display conditions first, then note the location, shape, and behavior of any anomaly on other solid-color screens.
- Turn off night mode, eye-care mode, automatic color temperature, and extensions that alter colors.
- Keep a straight viewing angle and fixed distance; inspect the center first, then scan edges and corners slowly by row and column.
- If you see an unusual pixel, recheck it on red, green, white, and black backgrounds so dust, reflections, or page controls are not mistaken for a defect.
Scope
This tool generates a fixed pure-blue background for a quick visual check. It is not a colorimeter, gamut-measurement tool, or operating-system diagnosis page. Browser color management, screen modes, overlays, and panel processing affect visual appearance; use suitable instruments for quantitative color work.
Privacy and implementation
This tool runs entirely in the browser. It uploads no input, calls no remote API, and loads no third-party runtime resource.
The tool uses standalone HTML, CSS, and JavaScript and includes no third-party runtime library.
Frequently asked questions
How do I open a pure-blue full screen?
Choose whether you want a timer, then select Enter blue full screen. The controls hide automatically; press H or move the pointer to show them again.
Which dead pixels can a blue full screen reveal?
A pure-blue background can reveal dark pixels that do not emit blue, bright pixels, and pixels stuck on an unexpected color. Recheck with red, green, white, and black backgrounds.
How is this blue screen different from the Windows blue screen?
This page deliberately outputs a blue color background. A Windows blue screen is an operating-system failure view; the two have different purposes and responses.