Monitor Ghosting Test
Watch moving blocks for trails, smearing and inverse ghosting.
Track a moving block with your eyes rather than staring at one spot — smearing is easiest to judge while your eyes follow the object.
Your test runs locally in your browser. No device data is uploaded.
How to use the ghosting test
Pick a speed and follow one of the moving blocks with your eyes rather than staring at a fixed point on the screen. Eye-tracked motion is how you actually watch games and video, and it is where smearing is most visible. Go fullscreen for the longest possible travel, and try each background: dark objects on light show ghosting differently from light on dark.
What this test checks
Two separate effects appear on the same moving edge. Ghosting is the panel being slow to change a pixel, leaving a faint trail behind the object. Persistence blur is the pixel holding its colour for the whole frame while your eyes keep moving, which smears the object even on a panel with fast transitions.
A bright halo in front of or behind the block rather than a dark trail is inverse ghosting, which means the monitor's overdrive is set too aggressively. That is a setting rather than a defect, and turning overdrive down usually removes it.
What the browser can and cannot tell you
The animation is drawn at your display's refresh rate, so this test cannot push a panel faster than the browser can draw. It is reliable for spotting visible trailing and inverse ghosting, and for comparing overdrive settings against each other. It cannot measure grey-to-grey response time in milliseconds, which needs a high-speed camera or a photodiode rig.
Frequently asked questions
- What is the difference between ghosting and motion blur?
- Ghosting is the panel being slow to change a pixel, so a faint trail follows a moving object. Motion blur is the pixel holding its colour for the whole frame while your eyes keep moving, which smears the object even on a fast panel. Both appear on the same moving edge, which is why one test covers them.
- How should I watch the test?
- Follow a moving block with your eyes rather than staring at a fixed point. Eye-tracked motion is how you actually watch games and video, and it is where smearing is most visible.
- Can ghosting be fixed?
- Sometimes. Most monitors have an overdrive or response time setting: raising it speeds up pixel transitions, but too much causes inverse ghosting, a bright halo instead of a dark trail. Step through the levels and pick the highest one with no halo.
- Does the browser limit this test?
- Yes. The animation runs at your display refresh rate, so a very fast panel cannot be pushed harder than the browser can draw. It is good for spotting obvious trailing, not for measuring response time in milliseconds.