Test Your Screen.
Instantly.
Check your display for dead pixels, backlight bleed, color issues, gradients and more — directly in your browser.
Display Tests
Select an individual diagnostic test or launch the automated inspection sequence.
Dead Pixel Test Pro
Inspect your display for stuck, dead, or hot pixels across high-contrast solid colors and grays.
Backlight Bleed Test Pro
Inspect LCD displays for uneven light leakage, edge clouding, and IPS corner glow.
Color Test
Evaluate primary, secondary, and custom solid colors for hue uniformity and color rendering.
Gradient & Banding Test Pro
Check for color banding, gradient smoothness, and digital bit-depth quantization artifacts.
ScreenCheck Reference Pattern
Comprehensive all-in-one diagnostic reference pattern for geometry, sharpness, pixel mapping, grayscale, and color.
Stuck Pixel Test
Identify locked or anomalous subpixels with high-contrast color switches and optional pixel color cycling.
Subpixel Inspection
Inspect subpixel rendering, stripe layouts (RGB vs BGR), and text fringe clarity.
1:1 Pixel Mapping Test
Reveal interpolation, non-native scaling, and sharpness artifacts with 1px checkerboards.
Panel Uniformity Test
Inspect edge-to-edge brightness and color tint consistency across 10% to 90% grayscale fields.
Dirty Screen Effect Test
Expose panel clouding, vertical banding, and DSE with smooth panning grayscale fields.
Viewing Angle Test
Evaluate gamma shift, color tint degradation, and contrast loss from off-axis angles.
Inversion / Pixel Flicker Pattern
Check panel pixel inversion voltage balancing and avoid visible pixel shimmer or crosstalk.
RGB / CMY Color Suite
Inspect primary and secondary color purity, channel clipping, and saturation ramps.
Grayscale & Tonal Ramp Test
Assess grayscale neutrality, tonal transitions, and step distinction across continuous and stepped ramps.
Gamma Calibration Test
Visually estimate display gamma curve (1.8, 2.0, 2.2, 2.4) using mathematical luminance matching.
Black Level & Shadow Crush Test
Determine whether near-black shadow detail is being crushed into solid black.
White Saturation & Highlight Clipping Test
Verify that bright highlight tones remain distinguishable without clipping.
Visual Contrast Test
Inspect simultaneous near-black, mid-tone, and near-white steps on one screen.
Shadow Detail Test
Examine subtle dark gradients and geometric contours in low-luminance scenes.
Highlight Detail Test
Evaluate bright geometric contours and high-luminance detail retention.
Digital Color Separation Test
Visually inspect whether adjacent digital RGB shades remain distinguishable.
Dithering & FRC Inspection
Detect temporal Frame Rate Control (FRC) and spatial dithering noise on fine gradients.
Sharpness & Oversharpening Test
Identify white haloing, edge ringing, or blurry text caused by monitor sharpness settings.
Text Clarity & Subpixel Antialiasing
Inspect font rendering sharpness across font sizes, weights, and contrast themes.
Fine Line & Spatial Frequency Test
Examine 1px and 2px vertical, horizontal, diagonal, and crosshatch line rendering.
Checkerboard Pattern Test
Test spatial frequency and scaling with 1x1, 2x2, 4x4, 8x8, and 16x16 pixel blocks.
Geometry Grid & Alignment Test
Check for geometric distortion, non-linear stretching, and alignment with precision grids.
Aspect Ratio & Scaling Verification
Verify proper 16:9, 16:10, 21:9, and 32:9 proportions without stretching.
Visual Calibration Assistant
Step-by-step visual calibration procedure for monitor brightness, contrast, gamma, and sharpness.
OLED Near-Black Test
Inspect digital quantization, shadow crushing, and black uniformity across low luminance levels 0 to 32.
OLED Uniformity & Low-Gray Banding
Inspect 1%, 2%, 3%, 5%, 10%, 20%, 50% dark gray and low-saturation RGB fields for vertical banding and tinting.
Image Retention Inspection
Controlled 2-stage visual inspection to detect temporary residual image persistence without panel stress.
Burn-In Inspection Pattern
Screen-wide primary, secondary, and stepped gray fields with optional alignment grids to spot persistent uneven wear.
OLED Gradient & Quantization Test
Inspect near-black banding, tonal posterization, and dark chrominance steps on self-emissive displays.
OLED Shadow Detail & Dark Scene Test
Synthetic low-luminance geometric dark scene to evaluate fine shadow gradations without copyright assets.
OLED Motion & Dark Transition Test
Evaluate emissive pixel transitions, near-black overshoot, and sample-and-hold eye tracking blur.
HDR Environment & Capability Check
Validate browser HDR media queries, wide-gamut signaling, Canvas P3 support, and system pipeline state.
HDR Reference Pattern
ScreenCheck original comprehensive HDR test chart with near-black steps, highlight ramps, and color wedges.
HDR Gradient & 10-Bit Test
High bit-depth smooth and stepped gradients across White, RGB channels, and color temperatures.
HDR Highlight Clipping Test
Progressively bright digital highlight patches (Level 240 to 255) to visually inspect specular highlight detail.
HDR Black Level Test
Inspect HDR near-black threshold steps, mixed contrast, and dark gradient transitions.
HDR Shadow Detail Test
Original synthetic high-contrast scene to evaluate dark-region shadow detail alongside specular highlights.
HDR Color Gradient Test
Saturated primary and secondary color gradients across Red, Green, Blue, Cyan, Magenta, Yellow.
Wide Color Gamut Reference (sRGB vs P3)
Direct side-by-side comparison between standard sRGB and Display-P3 wide color gamut swatches.
HDR Banding Inspection
Inspect quantization banding across dark, mid-tone, and highlight gradients in HDR mode.
SDR vs HDR Demonstration
Educational demonstration explaining dynamic range, highlight detail, tone-mapping, and color volume.
HDR Motion Test
Evaluate motion clarity of bright highlights traveling across dark high-contrast backgrounds.
Local Dimming Test
Evaluate full-array local dimming backlight behavior with pure dark backgrounds and controlled bright objects.
Blooming / Halo Test
Freely move bright highlights across black using mouse, touch, or arrow keys to inspect visible light bleed and halos.
Starfield Local Dimming Test
Procedural high-density starfield on pitch black to evaluate small highlight contrast and backlight zone clipping.
Moving Highlight Test
Bright object travels smoothly across black to inspect zone transition latency and trailing halos.
Local Dimming Transition Inspection
Specialized moving high-contrast patterns designed to make backlight zone switching boundaries visually apparent.
Subtitle Blooming Test
Simulate high-luminance dialogue subtitles over deep black letterbox bars to inspect movie-watching halo effects.
Mixed Contrast Test
Simultaneous small highlights, large bright areas, near-black regions, and mid-tones in a single synthetic pattern.
Motion Lab
Analyze refresh behavior, motion clarity, ghosting and frame pacing directly in your browser.
Refresh Rate Test
Estimate your display’s effective refresh rate and frame interval stability using high-precision browser timing.
FPS Comparison
Compare moving objects simultaneously rendered at 30 FPS, 60 FPS, 120 FPS, and higher refresh rates.
Ghosting Test
Inspect panel pixel transition lag and trailing artifacts behind high-contrast moving objects.
Inverse Ghosting & Overshoot Test
Identify bright or dark inverse halos (coronas) caused by aggressive monitor overdrive settings.
Screen Information
Live display parameters detectedRuns purely inside standard browser engines. No native executables, no electron bloat, and zero operating overhead.
No telemetry or tracking scripts. No screen capturing or image uploads. Your hardware diagnostics remain strictly on your local machine.
True 1:1 fullscreen pattern rendering with zero decorative interference or gradients over active diagnostic fields.
Frequently Asked Questions
Why should I test a brand new monitor or laptop?
Manufacturers adhere to ISO dead pixel policies that may allow a certain number of defective subpixels. Testing immediately after unboxing allows you to return or exchange a defective unit within the retailer replacement window.
How does ScreenCheck work without installing software?
ScreenCheck leverages modern HTML5 Canvas, CSS hardware acceleration, and the W3C Fullscreen API to present exact test patterns directly to your graphics pipeline.
What is the difference between Dead Pixels and Stuck Pixels?
Dead pixels are completely unpowered (appearing permanently black on bright backgrounds). Stuck pixels have one or more subpixels locked in an ON state (appearing permanently red, green, or blue).
Can browser tests automatically tell if my display is broken?
No browser has physical optical sensors to observe the external light emitted by a monitor panel. ScreenCheck provides precision diagnostic patterns so your eyes can inspect the hardware accurately.