Cyan Screen Test
Pure cyan (#00FFFF) full-screen display for stuck red pixel detection, green+blue channel verification, and display color accuracy testing.
Or press F11 · Mobile: double-tap
How to Use
Cyan as a Stuck Red Pixel Detector
Cyan is the complementary color of red. It is created by mixing green and blue sub-pixels at full intensity while keeping red completely off. This makes the cyan screen the most effective test for spotting stuck red sub-pixels — they stand out as vivid red or orange dots against the cool cyan background. It is also useful for detecting hot pixels (all three sub-pixels stuck on) which appear as white dots.
Cyan in Color Theory & Design
Cyan (#00FFFF) sits between green and blue on the visible spectrum and is one of the four process colors in CMYK printing (Cyan, Magenta, Yellow, Key/Black). Digital displays that accurately reproduce cyan are essential for photographers, graphic designers, and print professionals who need screen colors to match physical print output. A properly calibrated cyan should appear neither too blue nor too green — it should be a clean, balanced teal-blue tone.
What Each Anomaly Means on a Cyan Screen
Red dot
Red sub-pixel stuck ON — most common finding on cyan screen
Black dot
Dead pixel — all sub-pixels permanently OFF, hardware failure
White dot
Hot pixel — all three sub-pixels stuck ON simultaneously
Brightness patch
Screen uniformity issue — one area brighter/darker than another
Frequently Asked Questions
What is the cyan screen test used for?▼
The cyan screen test is primarily used to detect stuck red sub-pixels, which appear as vivid red dots against the cyan background. It also tests green and blue channel uniformity, checks for dead pixels (black dots), and helps verify that your monitor can accurately reproduce the CMYK cyan color reference (#00FFFF).
Why does my cyan screen look blue or green?▼
Cyan should be an equal mix of green and blue. If it looks too blue, your blue channel gain is higher than your green channel. If it looks too green (teal-heavy), the green gain is dominant. Adjust the RGB balance in your monitor's OSD settings. Alternatively, your monitor's color temperature preset may be shifting the balance — try switching between preset modes like sRGB, AdobeRGB, or Native.
Is cyan the same as teal or turquoise?▼
Not exactly. Pure cyan (#00FFFF) is the maximum-saturation version — it is made entirely of green and blue channels at 100%. Teal and turquoise are less saturated, darker variants of cyan used in design. For hardware testing purposes, pure cyan (#00FFFF) is the correct reference color as it maximally stresses both the green and blue sub-pixels.
Should I test cyan and magenta together?▼
Yes — cyan and magenta are complementary to each other. Cyan turns off the red channel; magenta turns off the green channel. Together with yellow (which turns off blue), these three secondary colors cover all possible stuck sub-pixel combinations. Running cyan, yellow, and magenta in sequence provides a complete sub-pixel fault analysis for any display.