Red Screen Test
Full-screen pure red (#FF0000) for stuck pixel detection, red color channel testing, and monitor calibration verification.
Or press F11 · Mobile: double-tap
How to Use
Understanding Pixel Failures on a Red Screen
Dead Pixel
Appears as a permanently black dot. The pixel is completely off and does not respond to any color signal.
Stuck Red Pixel
Shows as a brighter red dot or blends in — hard to spot. Check the green and blue screens where stuck red appears as a colored dot.
Stuck Green/Blue
On a pure red screen, a green or blue sub-pixel stuck ON shows as a cyan, green, or blue dot — easy to identify.
Red Channel & Color Accuracy
The red channel controls all warm tones in your display — skin tones, sunsets, and fire effects depend on accurate red reproduction. A properly calibrated red screen should appear pure and saturated without any orange or pink tint. If the red looks washed out or shifted toward orange, your monitor may need color calibration using your display's OSD (On-Screen Display) menu or display calibration software.
Red Light for Night Vision
Red light has less impact on night-adapted vision than white or blue light. Astronomers, military personnel, and photographers use red light to preserve night vision while still being able to see. Setting your monitor to a red screen at low brightness (15–25%) is useful when working in dark environments — it illuminates your workspace without destroying your eyes' dark adaptation.
Frequently Asked Questions
What does a stuck red pixel look like?▼
A stuck red pixel is permanently lit in red and may be difficult to see on a red screen. Run the green and blue screen tests — the stuck red sub-pixel will appear as a colored dot (red or orange) against the different background colors. On a white screen, stuck pixels appear as bright single-color dots.
How do I fix a stuck red pixel?▼
Try pixel-fixing software that rapidly cycles colors to stimulate stuck pixels back into normal operation. Gently pressing on the affected area with a soft cloth while the display is off can sometimes help. Note: this works for stuck pixels (always one color) but not dead pixels (always black), which are a hardware failure.
Why does my red screen look orange or pink?▼
An orange tint suggests the green channel is slightly mixed in. A pink tint indicates the blue channel is blending with red. This usually means your display color temperature or RGB balance is miscalibrated. Adjust the red, green, and blue sliders in your monitor's OSD settings or use a hardware color calibrator for accurate results.
Can I use a red screen to protect my sleep?▼
Yes. Red light has the least impact on melatonin production compared to blue and white light. Using a red screen at low brightness in the evening is much gentler on your circadian rhythm than blue-heavy displays. Many night mode settings try to shift toward warmer tones for this reason.
What is a bright red screen used for?▼
A bright red screen is commonly used for stuck pixel detection, monitor color calibration, night vision preservation, photography dark room work, and ambient red lighting. At full brightness, a red screen makes non-red pixels — including dead pixels and stuck sub-pixels — immediately visible as dark or colored dots against the pure red background.
How do I get a full red screen on my monitor?▼
Open this page and click the fullscreen button or press F11. Your entire monitor will display a full red screen instantly — no download or software needed. Works on PC, Mac, laptop, tablet, and phone. You can also adjust the brightness slider to control the intensity of the red display.