How to use the monitor test
- Dim the room lights and let the screen warm up for a few minutes.
- Press Start monitor test. The first pattern fills the whole screen.
- Tap the screen, press the right arrow or press Space to move to the next pattern. Use the left arrow to go back.
- On each pattern, look for the faults listed in the table on this page.
- Press Esc or exit fullscreen to finish.
What to look for on each pattern
| Pattern | What it checks | A fault looks like |
|---|---|---|
| Gray gradient | Banding and smooth shading | Hard vertical stripes instead of a smooth fade |
| Color gradients | Banding in red, green, blue and gray | Steps or a tint in one color band |
| Color bars | Basic color reproduction | A missing or wrong bar, or a color that looks washed out |
| Gray steps | Shadow and highlight detail | The darkest or brightest steps merge together |
| Grid and geometry | Aspect ratio, scaling and overscan | Stretched squares, an oval circle, a cropped border |
| Checkerboard | Native resolution and scaling | Blur, shimmer or moire instead of a fine even texture |
| Sharpness text | Text clarity and filtering | Fuzzy or colored edges on small text |
Who this is for
- Buying or selling a monitor or TVRun the patterns on the spot to catch banding, bad scaling and cropped edges before money changes hands.
- Setting up a new displayCheck the resolution, scaling and picture mode are right before you trust the screen for work.
- Photo and video editorsSee whether shadows and highlights hold their detail and whether gradients stay smooth.
- GamersCheck the gray steps so dark scenes are not crushed and the grid so the picture is not stretched.
- Home theater and projector usersFind overscan and geometry problems and set picture modes properly.
- IT and support staffA quick set of known patterns to separate screen faults from cable, driver or setting issues.
Frequently asked questions
What can a monitor test show that a dead pixel test cannot?
A dead pixel test fills the screen with solid colors, which reveals faulty pixels. The patterns here check other things: smooth gradients show color banding, gray steps show whether dark and light shades are separated, the grid shows geometry and scaling problems, and fine text shows sharpness.
What is color banding and how do I spot it?
Banding is visible stripes in what should be a smooth fade. Open the gray gradient and look for hard vertical bands instead of a seamless blend. A little banding is common on 6-bit and low-end panels. Strong banding in the colored gradients can also point to a wrong color depth or cable setting.
Why do the first gray steps look the same on my screen?
If the darkest two or three steps merge into pure black, the screen is crushing shadow detail. Raise the brightness or contrast a little, check that the video range is set to full on Windows or your graphics card, and compare again. The brightest steps merging points to contrast set too high.
How do I know whether the grid shows a geometry problem?
Every square should look the same size and the circle in the middle should look round. Squares that are stretched mean the screen is running at the wrong aspect ratio or resolution. On a flat panel the lines should be straight to the edge, with the border visible on all four sides.
The border of the grid is cut off. Why?
Some TVs and projectors zoom the picture slightly, a setting often called overscan. Look for a mode named Just Scan, Screen Fit, 1:1 or PC mode in the picture settings, then check that all four border lines show.
What is the checkerboard pattern for?
It alternates single pixels between black and white. On a screen running at its native resolution it looks like an even fine gray texture. Blur, shimmering or visible moire patterns mean the picture is being scaled, or that a sharpness filter is on.
Does the sharpness text pattern work on phones?
Yes. It shows black text on white and white text on black at several sizes. If the smallest lines look fuzzy or colored along the edges, check display scaling and any sharpness or text smoothing setting. Hold your phone at a normal reading distance.
Do I need to calibrate my screen before using this?
No. The patterns are for spotting faults and settings problems, and they work on any screen. A calibration tool with a measuring device is a separate job. For the best judgment, dim the room, let the screen warm up for a few minutes and turn off auto brightness.