Free Online Monitor Test

Grayscale Gradient Test

Test monitor grayscale banding, 8-bit vs 10-bit smoothness, and 0%-10% shadow detail online for free. Compare contouring, black crush, and dark-scene visibility before you change your monitor.

Module A

Smoothness & Banding Test

Compare 8-bit and 10-bit ramps side by side. Lower counts expose banding faster.

8-bit Reference Up to 256 grayscale steps
10-bit Reference Up to 1024 grayscale steps
Stress Test Levels
Current Profile 256 levels | Focus: 8-bit

Start with 256 levels first. Mild stripes can come from the display chain rather than the panel alone.

256-level grayscale selected. Minor vertical or horizontal contour lines can come from the operating system, GPU, cable, browser, or panel chain, not only the monitor itself.

Banding Guide

Why you may see banding

  1. Confirm the cable and port support full color depth: HDMI 2.0/2.1 or DP 1.4+.
  2. Check the operating system output depth and make sure the GPU is not falling back to 6-bit.
  3. Keep HDR off during this test. SDR gamma is the correct baseline for grayscale inspection.
  4. Use 32 or 128 levels to stress the chain. If low-count ramps stay clean but 256 shows contouring, the source path may be the bottleneck.
  5. Remember that many fast gaming panels use 6-bit + FRC. Light ripple in extreme grayscale tests can still be normal.

What To Expect

8-bit vs 10-bit reference

  • 8-bit paths top out at 256 grayscale steps, so visible color bands are easier to trigger in long gradients.
  • 10-bit paths can map the same ramp into 1024 steps, which reduces hard contour edges and improves dark transitions.
  • If you see slight “onion ring” bands, do not assume the monitor is defective before you finish the checklist above.

Module B

Shadow Detail Test

Inspect a 0%-10% black grid to spot black crush and missing shadow detail.

Background
Visibility Self-Check
Use a dark room and normal daily brightness. If the 0%-4% blocks disappear entirely, the display chain or panel tuning may be crushing shadow detail into black.

How To Read It

Shadow detail workflow

  1. Dim the room and keep monitor brightness near your normal daily setting, not maximum.
  2. Try to identify the hidden numbers in each square without leaning too close to the panel.
  3. If 0%-4% is fully missing, black crush is likely present.

KTC Tip

Try Black Equalizer

If you use a KTC gaming monitor, enable Black Equalizer in the OSD and re-check the darkest squares. It can lift shadow detail without washing out the whole image, especially in FPS scenes.

Monitor Test Hub

Run More Display Diagnostics

Pair grayscale testing with motion clarity, dead-pixel, and backlight checks before you decide whether the issue is in the source chain or the panel.

Motion Clarity

Motion Clarity Test

Compare refresh-rate smoothness, ghosting, and moving-text readability before you decide whether a panel issue is really motion tuning.

Open Motion Clarity Test

Pixel Checker

Dead Pixel Checker

Cycle pure black, white, red, green, and blue screens to inspect dead, stuck, or dim pixels before daily use.

Open Pixel Checker

Backlight Bleed

Backlight Bleed Test

Use a neutral gray fullscreen panel to inspect corner glow, edge brightening, and uneven backlight distribution.

Open Backlight Bleed Test

FAQ

What is Color Banding and Why Does it Happen?

Use these topics to expand the tool into page-level SEO content and explain how grayscale smoothness relates to real-world gaming, editing, and video playback.

8-bit vs 10-bit vs 12-bit: Real Differences in Gaming and Content Creation

Higher bit depth increases the number of visible grayscale and color transitions, which reduces harsh contour edges in skies, shadows, and HDR-like gradients.

What is Black Crush and How to Fix It

Black crush happens when the darkest values clip together. It can come from gamma tuning, limited-range output, HDR mismatch, or overly aggressive shadow handling.

Monitor Viewing Angles: IPS vs VA vs TN vs OLED

Panel technology affects how evenly dark tones hold together across the screen. Viewing-angle shifts can make gradients or shadow grids look worse than they really are.

How to Calibrate Monitor Brightness for Shadow Detail

Shadow testing should happen near real use brightness. Max brightness can hide black crush or make low-end separation appear cleaner than normal.

Color Banding in Streaming vs Local Content

Compression artifacts, browser playback, and source mastering all affect gradients. A visible band does not always mean the monitor panel itself is the culprit.