How to use the ghosting test
A ghosting test moves objects across your screen at fixed speeds so you can see trails (ghosting), bright halos (overshoot) and blur. This one moves them by whole pixels every frame at your refresh rate, so what you see comes from your monitor.
- Set your screen to its top refresh rate. Check it first with the refresh rate test.
- Press Full screen so nothing else moves on the screen.
- Start on Gray, then try Black and Dark gray. Dark backgrounds show dark smearing best.
- Follow one object with your eyes. Look at the edge behind it, not at the whole lane.
- Switch to the Text object to see how readable moving text stays.
- Rate each overdrive setting in Overdrive notes, then copy your notes.
Give each setting about a minute and watch the same lane every time. Your notes stay in this browser, so you can come back after restarting the monitor.
Ghosting, overshoot or motion blur? How to tell
Monitor ghosting is one of several motion artifacts. They look alike at first, but each has its own cause and fix.
Trails and halos sit behind the moving edge, so follow the object with your eyes and look there. Blur is even on both edges and gets shorter at higher refresh rates. Copies, splits and jumps come from timing, not from the pixels.
| What you see | Name | Normal? | What to do |
|---|---|---|---|
| Faded trail behind the object | Ghosting (slow pixel response) | A short, faint trail is common on LCDs | Raise overdrive one step. Long dark trails on dark backgrounds are typical VA smearing. |
| Bright or colored halo | Overshoot (inverse ghosting) | No | Lower overdrive one step. |
| Soft, even blur on both edges | Motion blur (persistence) | Yes | Higher refresh rates or a strobing mode reduce it. |
| Two or more copies | Strobe crosstalk, or a double image | No | With strobing on, lower the strobe setting. Otherwise, check the refresh rate. |
| Edges split sideways | Screen tearing | Not a panel fault | Run the screen tearing test. |
| Jerky jumps | Stutter (dropped frames) | Not a panel fault | Close other apps, then check the refresh rate. |
The What do you see? buttons in the tool give the same answers, with the normal blur for your own screen.
How the ghosting test works
Each lane moves its object by a whole number of pixels on every frame. The speed is pixels per frame times your refresh rate, so 7 px per frame at 144 Hz is 1,008 px per second. Whole steps make every frame look the same, which keeps the test fair.
Even a perfect screen blurs a moving object while your eyes follow it. The blur equals the speed divided by the refresh rate: at 960 px per second, that’s 16 px at 60 Hz, 7 px at 144 Hz and 4 px at 240 Hz. Each lane label shows this number, so the page doubles as a motion blur test.
A browser can’t measure pixel response time in milliseconds. Reviewers use light sensors or high-speed cameras for that. A “1 ms” spec usually describes the fastest color change or a strobed mode, not every transition.
Ghosting at 144 Hz, 240 Hz and above
Higher refresh rates cut motion blur, but pixels must also change faster. They get 6.9 ms per frame at 144 Hz and only 4.2 ms at 240 Hz. A slow panel can trail more at a high rate than at 60 Hz, so test each rate you use.
How to fix monitor ghosting
Change one thing at a time and compare the same lane on the same background.
- Use the top refresh rate. A higher rate shortens the blur on every panel.
- Change overdrive one step at a time. Monitor menus call it Overdrive, Response Time, OD, Trace Free or AMA. The middle setting is often the cleanest, and the highest often adds halos.
- Expect some VA smearing. VA panels trail on dark backgrounds, and no setting removes it completely.
- Try a strobing mode such as ULMB, DyAc, ELMB or black frame insertion. It cuts blur, but it dims the picture and can add faint copies called crosstalk.
- On a TV, turn on Game Mode and turn off motion smoothing.
- Use a digital cable. Faint copies beside still text on a VGA cable come from the analog signal, not from motion. Use HDMI or DisplayPort.
- Return a new monitor if strong trails remain at every setting. Compare reviews of the same model first.
Overdrive can behave differently at each refresh rate, so check again after you change the rate. Write down the cleanest setting for every rate you play at.
Using this page as a UFO-style test
Searches for a “UFO test” usually mean TestUFO by Blur Busters, which made moving-object tests popular. This page is independent and isn’t affiliated with Blur Busters. The steps work the same way, whether you run a UFO test at 144 Hz or 240 Hz.
Open full screen, follow a moving object and compare settings. For photos, use Blur Busters’ pursuit camera method, or record 240 fps slow-motion video and step through it frame by frame.
Dropped frames make any moving-object test look jerky, on any site. The validity line under the lanes tells you whether the motion stayed smooth while you watched.
Ghosting test on phones, laptops and TVs
OLED phones show almost no ghosting, because their pixels switch very fast. They still show motion blur at 60 or 120 Hz. Laptop panels are often slower, and most have no overdrive setting.
On a phone, turn the screen sideways for longer lanes and tap the lanes to pause. Plug in a laptop before you test, because battery modes can lower the refresh rate.
For a TV, open this page in the TV’s browser or cast it, and turn on Game Mode. OLED TVs can also show burn-in, which an OLED burn-in test checks.
Looking for keyboard ghosting instead? The keyboard ghosting test checks whether a keyboard misses key presses, which anti-ghosting keyboards are built to avoid.