Refresh Rate Test

Refresh rate (measured in Hz) is the number of times per second your monitor updates the image on screen. A 60Hz monitor refreshes 60 times per second, while a 144Hz monitor refreshes 144 times. Higher refresh rates result in smoother motion, reduced motion blur, and lower input lag — especially noticeable in fast-paced games, scrolling, and video playback. However, many users buy high refresh rate monitors without realizing their system may default to 60Hz. Running a refresh rate test ensures your monitor is operating at its maximum advertised frequency.

You can check your monitor refresh rate using our online refresh rate test above — simply click "Start Test" and the tool measures your actual display refresh rate in real time using the browser's requestAnimationFrame API. Alternatively, you can check through your operating system: on Windows, go to Settings > System > Display > Advanced display settings. On macOS, go to System Settings > Displays. However, OS-reported refresh rates may not always match the actual output — our browser-based Hz test gives you the real number your display is producing.

Ghosting is a visual artifact where fast-moving objects leave visible trails or "ghosts" on screen, caused by slow pixel response times. It is especially common on VA panel monitors. To test for ghosting, use the UFO test above — enable "Show UFO" and watch the moving UFO. If you see a visible trail behind the UFO, your monitor has ghosting. You can adjust the speed to test at different motion velocities. Ghosting can often be reduced by enabling your monitor's overdrive or response time setting in the OSD (on-screen display) menu.

Frame skipping occurs when your monitor fails to display every frame sent by the GPU, resulting in stuttery motion. This can happen when the monitor's refresh rate is set higher than its physical capability, or due to cable bandwidth limitations (e.g., using HDMI 1.4 for 144Hz at 4K). Our refresh rate test monitors the interval between frames and flags any frames that arrive significantly later than expected. If the "Frame Skips" counter increases during testing, your monitor is skipping frames. Try lowering the resolution, using a DisplayPort cable instead of HDMI, or reducing the refresh rate setting.

Frame rate (FPS) is how many frames your GPU or browser renders per second; refresh rate (Hz) is how many times your monitor updates the screen per second. They only match when both sides keep up. Our test measures the browser rendering frame rate through requestAnimationFrame, which normally follows the display refresh rate — for example 60fps on a 60Hz screen or 144fps on a 144Hz screen. If your GPU cannot render fast enough, the measured number drops even though the monitor may still support a higher Hz. The UFO ghosting test above is a motion-clarity check, not an FPS benchmark: it shows whether moving objects leave trails (ghosting), smear on dark transitions (black smearing), or jump because frames were skipped.

The UFO test is a moving-target pattern popularised by TestUFO and Blur Busters, and it judges motion clarity rather than speed. Watch the object at your normal viewing distance: a crisp leading edge with a short faint trail is a healthy panel, a long dark halo is ghosting, a smeared shadow on dark transitions is black smearing, and an object that jumps in steps is frame skipping. The image should look clearly sharper at 144Hz than at 60Hz, which is why gaming panels at 144Hz, 240Hz or 360Hz gain the most, while OLED shows almost no trail thanks to near-instant pixel response. It is a visual check, so read it alongside the measured Hz and the stutter count rather than as a score.

If your 144Hz monitor shows 60Hz in our test, the refresh rate has not been properly configured in your operating system. On Windows, go to Settings > System > Display > Advanced display settings and change the refresh rate from 60Hz to 144Hz. On macOS, go to System Settings > Displays and select the higher refresh rate. Also ensure you are using a cable that supports high refresh rates — DisplayPort 1.2 or HDMI 2.0 are typically required for 144Hz at 1080p. Some older HDMI cables (1.4) only support 60Hz at 1080p. After changing the setting, run the test again to verify.

No. This tool is read-only — it measures and displays your current refresh rate but cannot change it. To change your refresh rate, use your operating system settings: on Windows, go to Settings > System > Display > Advanced display settings > Refresh rate. On macOS, go to System Settings > Displays and select a refresh rate. After changing the setting, run our test again to verify the new refresh rate is active. Some monitors also allow refresh rate changes through the OSD (on-screen display) menu.

No. This is a diagnostic tool, not a repair tool. It cannot adjust your monitor's overdrive settings, change response time modes, or fix cable bandwidth issues. What it can do is help you detect whether ghosting, motion blur, or frame skipping is occurring so you can take corrective action. To fix ghosting, enable overdrive in your monitor's OSD menu. To fix frame skipping, use a DisplayPort cable instead of HDMI, lower the resolution, or reduce the refresh rate setting. Run our test after each change to verify the improvement.

Yes. This tool works perfectly for testing laptop displays. Many modern gaming laptops advertise 144Hz or 240Hz screens, but sometimes the system defaults to 60Hz to save battery. Run our refresh rate test to verify your laptop screen is running at its advertised refresh rate. If it shows 60Hz, check your display settings and ensure you are not in a power-saving mode that caps the refresh rate. Some laptops also use variable refresh rate technology that adjusts the Hz dynamically based on content.

Yes, but with limitations. Most mobile devices have fixed refresh rates (60Hz or 120Hz) that are controlled by the operating system. Our tool will measure the actual refresh rate the browser receives, which on mobile is typically 60Hz or 120Hz depending on the device. Some high-end phones (iPhone Pro, Samsung Galaxy S series) support variable refresh rates that adjust based on content. Note that mobile browsers may cap the frame rate in certain situations, such as low battery mode.

Scroll judder usually comes from the software chain rather than from the panel. The common causes are a page whose animation loop is capped at 60fps, a browser or driver profile holding the display at 60Hz, a power saving state on a laptop, a background tab, an extension hooking the compositor, or motion smoothing on a TV-class screen. Work through them by elimination: keep this tab in the foreground, turn off battery saving, remove frame rate limiters, disable extensions, then re-run the test. The measurement is identical on Windows, macOS, Linux and ChromeOS in any current Chromium, Firefox or Safari build, which is what makes it useful for comparing one machine against another.