Blue Screen Test
Full-screen pure blue (#0000FF) for blue color channel verification, stuck pixel detection, and display color accuracy testing.
Or press F11 · Mobile: double-tap
How to Use
RGB Sub-pixel Diagnostics
Every pixel on your display contains three sub-pixels: red, green, and blue. Testing each pure color individually reveals which sub-pixel has failed and how. On a pure blue screen:
- • Yellow dot — red + green sub-pixels stuck ON, blue is off
- • Red dot — only red sub-pixel stuck ON
- • Green dot — only green sub-pixel stuck ON
- • White dot — all three sub-pixels are stuck ON
- • Black dot — dead pixel, all sub-pixels permanently OFF
Blue Light & Display Health
Blue light (wavelength 415–455nm) from displays is known to suppress melatonin and contribute to digital eye strain. Modern monitors use blue-light filters and warm color modes to reduce this. When testing your blue channel, a well-calibrated display should show pure, deep blue — not a purple or cyan tint. If the blue appears washed out, your monitor's blue channel gain may need adjustment via the OSD settings.
Blue as a Chroma Key Color
Before green became the standard chroma key color in digital video, blue screen was the original chroma key background used in film and TV production since the 1940s. Blue screens are still preferred for subjects wearing green clothing, or when shooting outdoors with green foliage in the scene. This pure blue (#0000FF) screen can serve as a chroma key background when green isn't suitable for your specific shot.
Frequently Asked Questions
Why does my blue screen look purple?▼
A purple tint on a pure blue screen means the red channel is bleeding into the blue. This indicates your monitor's color balance is off — the red gain is too high or the blue gain is too low. Adjust the RGB balance in your monitor's OSD (On-Screen Display) menu. Professional calibration tools like a colorimeter can fix this precisely.
What is a stuck blue pixel?▼
A stuck blue pixel is a sub-pixel permanently lit in blue. On a white or yellow background it appears as a blue dot. On the blue screen itself it blends in — test on a red or green screen where it will show as a blue or cyan-colored spot. Stuck pixels can sometimes be fixed by pixel-cycling software or gentle pressure.
Is blue screen the same as BSOD (Blue Screen of Death)?▼
No. The Windows Blue Screen of Death (BSOD) is a system crash error screen — it has nothing to do with display hardware. This blue screen test is a pure display hardware test showing a solid blue color to check your monitor's blue channel and pixel health.
How does blue light affect sleep?▼
Blue light suppresses the production of melatonin (the sleep hormone) more than any other color. Avoiding screens 1–2 hours before bed, using night mode, or enabling blue light filters can significantly improve sleep quality. Our blue screen test is for hardware testing only — we recommend minimizing blue light exposure in the evening.
Can I get a blank blue screen or full blue display on my PC or computer?▼
Yes. This tool gives you a blank blue screen and full blue display instantly on any PC, Mac, laptop, or computer. Open the page and click fullscreen — your entire computer blue screen or pc blue screen fills the display. Works in Chrome, Firefox, Edge, and Safari.
What is the difference between a dark blue screen and a light blue screen?▼
A dark blue screen uses a lower brightness setting and appears deep navy or midnight blue — useful for dark environments and night vision preservation. A light blue screen is the same pure blue at higher brightness. Use the brightness slider on this page to switch between dark blue screen and light blue screen modes.
Is this a fake blue screen or the real Windows BSOD?▼
This is not a fake blue screen of the Windows crash type — it is a pure solid blue display for monitor testing purposes. The Windows BSOD (Blue Screen of Death) shows error text and codes. This blue screen view is simply a color test tool with no error messages, completely safe to use.