What Is the UFO Motion Test?
The UFO Motion Test is a visual comparison tool that shows horizontally scrolling objects (UFO shapes) at different simulated refresh rates. By viewing multiple rows of motion simultaneously, you can directly compare the smoothness and clarity of motion at 60Hz, 120Hz, 144Hz, and your display's native refresh rate.
This test is inspired by the popular TestUFO concept but works entirely within your browser using the Canvas API — no external assets or plugins required.
Understanding Motion Blur and Pixel Response Time
Motion blur in LCD monitors comes from two sources: sample-and-hold blur (the pixel stays lit for the entire frame duration) and pixel response time (how quickly a pixel can change color).
Higher refresh rates reduce sample-and-hold blur because each frame is displayed for less time. A 60Hz display holds each frame for 16.67ms, while a 240Hz display holds each frame for only 4.17ms — resulting in significantly sharper motion.
However, pixel response time also matters. If your panel's pixel response is 8ms on a 144Hz display (6.94ms per frame), you'll see ghosting/trailing because the pixels can't transition fast enough. This is why 1ms response time panels exist for competitive gaming.
How to Get the Best Results
- Ensure your monitor is set to maximum Hz — the bottom row shows motion at your native refresh rate.
- Look at the UFOs, not the background — focus your eyes on the moving objects to perceive motion clarity.
- Adjust speed — faster speeds make refresh rate differences more visible.
- Compare the rows — the bottom row should look smoothest if your monitor supports high refresh rates.