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Check for dead pixels, bright spots and dark spots
Blue Screen Test
A pure blue field activates only blue subpixels — ideal for channel isolation, cool ambient lighting, and spotting defects that hide on mixed desktop content. Use fullscreen on monitors, phones, tablets, or TVs, then export a blue PNG when you need a still reference.
Blue Screen Test
A pure blue field activates only blue subpixels — ideal for channel isolation, cool ambient lighting, and spotting defects that hide on mixed desktop content. Use fullscreen on monitors, phones, tablets, or TVs, then export a blue PNG when you need a still reference.
Blue channel isolation
Reveal weak blue zones and subpixel failures specific to the blue path on LCD and OLED. Mixed wallpaper camouflages these; a pure blue field does not.
Stuck and dead pixel detection
Dark spots on blue suggest dead pixels; red or green pinpoints against blue often mean stuck subpixels on other channels worth documenting for warranty.
Cool ambient fill light
Fullscreen blue softens shadows for creative low-light setups and night streams — reduce brightness for comfort on long sessions.
Color temperature sanity check
Use with white and grey screens to see whether your panel’s white point drifts warm or cool after Night Shift, True Tone, or a new ICC profile.
About Blue Screen Test
Run a free fullscreen blue screen test to inspect the blue channel, find stuck or dead pixels, and check cool-tone uniformity on monitors, phones, tablets, and TVs.
Why blue matters in a pixel routine
Blue subpixels are smaller on many RGB layouts and can show wear or drive issues earlier. A dedicated blue page removes red and green so those problems are not camouflaged by wallpaper or browser chrome.
How to inspect a blue screen fairly
Dim the room, set a moderate brightness, and view from your normal distance. Fixed dots and fixed blotches matter; mild corner shifts with head movement may be normal for the panel type.
OLED vs LCD on blue
OLED can deliver deep, even blue with high contrast against dark UI chrome. LCD backlight structure may add soft clouds — separate that from single-pixel stuck dots that never move when you pan the window.
How to use the blue screen
A pure blue field activates only blue subpixels — ideal for channel isolation, cool ambient lighting, and spotting defects that hide on mixed desktop content. Use fullscreen on monitors, phones, tablets, or TVs, then export a blue PNG when you need a still reference.
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Open this blue screen page on any modern browser…
Open this blue screen page on any modern browser on desktop, phone, tablet, or TV.
Tip Use ← → to switch colors in the picker
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Enter fullscreen from the preview for a solid blu…
Enter fullscreen from the preview for a solid blue (#0000FF) background with no UI chrome in the way.
Tip Press F or click the preview for fullscreen
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Scan for dark dots, wrong-color sparks, or uneven…
Scan for dark dots, wrong-color sparks, or uneven blue clouds — then download a PNG or continue with red and green channel pages.
Tip Press Esc to exit fullscreen
Core testing tools
Continue your display QA with these linked diagnostics.
Dead pixel test → Solid-color fullscreen frame-by-frame scan. Detects bright, dark, and stuck pixels — the essential first step. Backlight bleed test → Pure black fullscreen in a dark room to detect LCD leakage and IPS glow. Color calibration test → Gamma ramps and greyscale steps for accuracy checks. Color gamut test → sRGB vs Display P3 patches for wide-gamut verification. Refresh rate test → Real-time Hz detection to verify your panel's actual refresh rate. Ghosting test → Moving blocks for response time and grey-to-grey transition speed. Uniformity test → Grey fields and grid overlay for vignette and tint checks. Display test center → Hub for customizable display QA — gradients, HDR, flicker, and more.
Blue screen tips
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Why blue matters in a pixel routine
Combine blue with red and green to map which channel owns a tint complaint before you change cables, update GPU drivers, or file a return.
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How to inspect a blue screen fairly
If blue only looks crushed in HDR or Game mode, retest in a standard SDR picture mode before concluding the panel failed. Photograph persistent dots straight-on for evidence.
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OLED vs LCD on blue
After blue, open black for bleed and white for dark dead pixels to finish a balanced pass. Use Start pixel test when you want an automatic multi-color cycle.
Specialized testing workflows
Step-by-step guides for devices, panel types, and color testing.
Fullscreen color test guide → Setup checklist, color sequence, and common mistakes for solid-field QA. Dead pixel how-to → White, black, and RGB passes with return-window documentation tips. Screen uniformity guide → Grey-field vignette, banding, and dirty-screen effect checks. Resolution & DPR guide → Verify native pixels, viewport, and device pixel ratio before pixel tests. Laptop screen test → 8-step laptop inspection flow. PWM flicker, gamut issues, and panel lottery — all covered. Mobile screen test → OLED burn-in, touch dead zones, PWM flicker — essential for used phone inspection. TV screen test → Mini LED blooming, backlight bleed, MEMC checks — must-do after new TV unboxing. Monitor screen test → IPS, VA, and OLED panel testing, PPI verification, and G-Sync/FreeSync validation. OLED screen test → Burn-in, PWM, ABL, black crush — comprehensive OLED-specific issue coverage. LCD screen test → IPS bleed, VA ghosting, Mini LED blooming — complete LCD panel evaluation.
More screen tools after Blue
Choose a solid color for pixel tests, monitor cleaning, chroma key checks, or ambient lighting.
Blue screen FAQs
What is a blue screen test?
A blue screen test fills the display with pure blue so you can inspect the blue channel for dead pixels, stuck subpixels, and uneven cool-tone brightness. TestMyGears runs it free in your browser.
What defects show on a blue screen?
Dead pixels appear dark; stuck pixels may show as red, green, or white dots against blue. Soft clouds can be backlight structure rather than bad pixels — note whether they stay fixed.
Is blue light from this tool harmful?
Emission follows your panel brightness. Lower brightness for long sessions and take breaks like any bright fullscreen — this page does not raise output beyond your settings.
Can I download a 4K blue wallpaper?
Yes — select 4K (3840×2160) or another preset (1080p, 8K, custom) and download PNG.
Should I test red and green too?
Yes. A full channel check uses red, green, and blue plus white and black for contrast and dead/stuck pixels. This page isolates blue; open the others or use Start pixel test.
Does it work on tablets and phones?
Yes, in browsers that support fullscreen and PNG download on phone, tablet, monitor, or smart TV.
Why does blue look different after Night Shift?
Night Shift and similar filters cut blue deliberately. Disable them for QA, then re-enable for everyday comfort — compare this same URL before and after.
Free to use?
Yes — TestMyGears requires no account.
Blue Screen Test
A pure blue field activates only blue subpixels — ideal for channel isolation, cool ambient lighting, and spotting defects that hide on mixed desktop content. Use fullscreen on monitors, phones, tablets, or TVs, then export a blue PNG when you need a still reference.
