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Refresh Rate Test & UFO Motion Test — Check Monitor Hz Online

Measure your screen refresh rate with a real-time requestAnimationFrame Hz counter, inspect frame time and stability, compare 30 FPS, 60 FPS and native motion, and run an original UFO-style smoothness test on monitors, laptops, phones and tablets.

60Hz to 360Hz+ Frame-time diagnostics No files or account
0 display tests completed New Fullscreen motion mode

Live screen refresh rate and motion analyzer

For the cleanest result, keep this tab visible, close heavy applications and let the selected test finish without switching windows.

Live motion
Estimated refresh rate— HzCollecting live frames
Nearest standard mode—60, 90, 120, 144, 165, 240…
Median frame time— msLower is faster
Frame stabilityWaitingRun the timed test
Native browser motion trackTrack the spacecraft with your eyes and look for blur, ghost trails or uneven jumps.
Mobile tip: rotate your phone to landscape or use Focus mode for the widest motion track.
Original CorrectionCopy motion pattern · measuring
Preparing measurement—
960 px/s
Live motion is running. Select a test length and press Start Accurate Test for a stable refresh-rate estimate.

Frame-time graph and smoothness strip

Each bar represents time between consecutive animation callbacks.

StableLateLarge delay

30 FPS vs 60 FPS vs native refresh

All lanes use the same speed; only update frequency changes.

30 FPS stepped
60 FPS standard
Native live Hz

On a 60Hz display, the 60 FPS and native lanes may look nearly identical. On 120Hz, 144Hz or faster screens, the native lane should advance in smaller, smoother steps.

Screen CSS size—
Viewport—
Pixel ratio—
Color depth—
Orientation—
Motion setting—

The test runs on your device. No files, screenshots or browsing history are uploaded. Completing a test updates only an anonymous aggregate test counter; submitting a rating updates the aggregate rating.

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Rate the monitor Hz checker and UFO motion test.

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How to Test Your Monitor Refresh Rate Online

Get a stable screen Hz estimate and inspect motion smoothness in three simple steps.

1

Prepare the display

Keep this browser tab visible, close demanding applications, disable battery-saving restrictions where possible and move the window onto the monitor you want to test.

2

Run the timed Hz test

Select 10 or 20 seconds and press Start Accurate Test. The tool warms up, samples frame intervals and estimates the active browser animation cadence.

3

Inspect motion and stability

Compare the 30 FPS, 60 FPS and native lanes, review the frame-time graph and smoothness strip, then repeat in fullscreen for a larger motion target.

Understand Your Refresh Rate Test Results

Refresh rate, frame time and frame pacing describe different parts of display motion.

ResultWhat it measuresHow to interpret it
Estimated refresh rate (Hz)The median frequency of foreground requestAnimationFrame callbacks during the timed sample.A value near 60, 90, 120, 144, 165, 240 or another configured mode usually indicates the browser is presenting animation near that cadence.
Nearest standard modeThe common display refresh rate closest to the raw estimate.Useful when the measured value is 59.94 instead of 60, 143.9 instead of 144 or similarly close to a standard mode.
Median frame timeThe typical milliseconds between consecutive animation frames.About 16.67 ms corresponds to 60Hz, 8.33 ms to 120Hz, 6.94 ms to 144Hz and 4.17 ms to 240Hz.
Stability scoreA practical score based on timing variation, late frames and large callback gaps.A high score means the browser delivered consistent frame intervals during this run; it is not a monitor response-time certification.
Smoothness stripA visual history of recent frame intervals.Mostly green cells indicate regular pacing. Orange or red cells indicate late callbacks, tab interruptions or temporary system load.
Motion comparisonThe same moving object updated at 30 FPS, 60 FPS and native browser cadence.Use eye tracking to compare step size and perceived smoothness. It can also reveal visible ghost trails, but does not quantify pixel response time.

Flagship Refresh Rate and UFO Motion Test Features

A complete browser-based display diagnostics page for everyday users, gamers, creators and device reviewers.

Robust requestAnimationFrame estimator

Uses median frame intervals and a warm-up period instead of relying on a single one-second frame count, helping reduce sensitivity to occasional timing spikes.

Live frame-time graph

See recent callback intervals in milliseconds with an ideal reference line and color-coded bars for normal frames, late frames and large delays.

Original UFO-style motion track

Track an independent spacecraft design at adjustable speeds to look for uneven motion, blur, overdrive trails or visible ghosting on the active display.

30, 60 and native comparison

Compare equal-speed motion updated at three cadences. Faster displays should show smaller motion steps in the native lane than in capped 30 FPS or 60 FPS lanes.

Fullscreen display testing

Expand the main motion track across the screen for easier eye tracking and testing from a normal viewing distance.

Private device-local analysis

No screenshot, video, file or browsing history is collected. Only anonymous aggregate test and rating totals use the site counter.

What Is a Refresh Rate Test?

A refresh rate test estimates how many times per second the active display pipeline can present a new browser animation frame. Refresh rate is expressed in hertz, or Hz. A 60Hz display can refresh up to 60 times per second, while a 144Hz monitor can refresh up to 144 times per second. This online monitor Hz test measures the cadence of requestAnimationFrame callbacks while the page is visible and converts the typical frame interval into an estimated refresh frequency.

The browser does not provide a universal, certified hardware refresh-rate property. For that reason, the number shown here is an estimate of the browser's active animation cadence, not a factory specification read directly from the monitor. When the system, browser and display are operating normally, the estimate often settles close to the configured refresh rate.

Refresh Rate vs FPS: What Is the Difference?

Refresh rate describes how often a display can update an image. Frames per second, or FPS, describes how many unique frames an application produces. A 144Hz monitor may refresh 144 times each second, but a game rendering only 60 FPS still produces 60 unique frames per second. Conversely, a game can render more frames than the display refreshes, which may increase responsiveness but can also produce tearing when synchronization is disabled.

This page uses FPS labels for the deliberately capped comparison lanes and Hz for the estimated display cadence. The native lane updates on every available animation callback, while the 30 FPS and 60 FPS lanes deliberately hold positions between updates.

60Hz vs 120Hz vs 144Hz vs 240Hz

At 60Hz, each refresh lasts about 16.67 milliseconds. At 120Hz, that interval is about 8.33 milliseconds. At 144Hz it is approximately 6.94 milliseconds, and at 240Hz it falls to about 4.17 milliseconds. Shorter intervals allow moving objects to advance in smaller steps and can reduce the time between an input and a visible update. Perceived improvement also depends on content frame rate, pixel response, motion speed, synchronization and the viewer.

How to Get the Most Accurate Monitor Hz Result

  • Keep the test in the foreground and do not switch tabs while measurement is running.
  • Close games, video encoders, heavy downloads and other applications that may create CPU or GPU spikes.
  • Connect the browser window to the exact monitor you want to test before starting.
  • Use fullscreen mode and a 20- or 30-second run when the reading is unstable.
  • Check operating-system display settings and confirm that the desired refresh rate is selected.
  • Connect laptops to power and disable aggressive battery-saving modes when testing high-refresh displays.
  • Repeat the test in another modern browser if a device appears capped at a lower value.

Why the Test May Show 60Hz on a 120Hz or 144Hz Screen

The display may actually be configured to 60Hz, the browser may limit animation cadence on that platform, the page may be embedded or backgrounded, hardware acceleration may be unavailable, a battery-saving feature may reduce animation frequency, or the cable and display mode may not support the intended refresh rate. Some systems also behave differently with multiple monitors that use different refresh rates.

What the UFO Motion Test Can and Cannot Show

The moving spacecraft and comparison lanes are useful for subjective smoothness checks. Follow the object with your eyes and observe whether its edges remain clear, smear, leave colored trails or jump unevenly. However, a browser animation alone cannot precisely measure monitor pixel response time, input lag, overshoot, persistence, PWM flicker or true frame skipping. Those measurements require controlled test patterns, a high-speed camera, a photodiode or other specialized equipment.

Variable Refresh Rate and Multi-Monitor Limitations

Variable refresh rate technologies can change the display cadence dynamically. Browsers, operating systems and graphics drivers may also choose different scheduling behavior when a window crosses displays or when several monitors use different modes. Move the window fully onto one display, wait briefly and run the test again. Treat a fluctuating result as an indication to repeat under cleaner conditions rather than as proof of a hardware fault.

Privacy and Browser Processing

Refresh-rate calculation, motion rendering, frame-time analysis and device-information display occur locally on your device. No image of your screen is captured. No files or personal content are uploaded. The page stores only your non-personal test preferences locally, such as motion speed and selected pattern. When a timed test finishes, an anonymous aggregate counter is incremented; ratings update an aggregate rating total.

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Refresh Rate Test Frequently Asked Questions

Answers about monitor Hz, FPS, UFO motion tests, frame timing and browser limitations.

Keep this page visible, select a 10- or 20-second test and press Start Accurate Test. The tool samples requestAnimationFrame timestamps, estimates the active animation cadence in hertz and shows the nearest common refresh-rate mode.

It provides a strong browser-based estimate when the page is in the foreground and the system is stable. It is not a hardware-certified measurement because browsers do not expose a universal direct monitor refresh-rate property and may apply platform-specific limits.

Hz is how many times a display can refresh each second. FPS is how many unique frames an application generates each second. They can match, but they describe different parts of the display pipeline.

Check the operating-system display setting first. Other causes include a browser or platform animation cap, battery saver, disabled hardware acceleration, unsupported cable or resolution mode, an embedded page, heavy system load or mixed-refresh multiple-monitor behavior.

Yes, when the browser and operating system allow requestAnimationFrame to run at the active display cadence. Use a longer test and fullscreen mode, and repeat in another browser when a high-refresh display appears capped.

The original moving spacecraft pattern helps you compare perceived smoothness and look for blur, trailing, colored overshoot or uneven motion while tracking an object. It is a visual check rather than a laboratory response-time measurement.

Green intervals are close to the recent median. Orange intervals are noticeably late, and red intervals are large delays that may represent dropped presentation opportunities, a busy system or a tab interruption.

Typical frame intervals are approximately 16.67 ms at 60Hz, 11.11 ms at 90Hz, 8.33 ms at 120Hz, 6.94 ms at 144Hz, 6.06 ms at 165Hz and 4.17 ms at 240Hz.

Fullscreen mainly makes the motion pattern easier to observe and can reduce surrounding visual distractions. It may help on some browser setups, but it does not guarantee a different or more accurate refresh-rate value.

You can visually inspect ghosting and motion blur, but the page cannot assign a reliable millisecond pixel-response number. Objective response-time, overshoot and input-lag measurements require specialized equipment or controlled high-speed-camera methods.

It can. Variable refresh rate, power management, browser scheduling and changing system load can produce varying frame intervals. Repeat the test and compare the median result and stability score rather than relying on a single momentary reading.

Yes. The interface is mobile-first, touch-friendly and designed for portrait or landscape use on modern phones and tablets, including 60Hz, 90Hz, 120Hz and adaptive-refresh screens. Focus mode provides a larger motion track. Mobile operating systems may still reduce animation cadence in low-power mode or cap some browsers.

No. This is an independent CorrectionCopy tool with an original spacecraft illustration, measurement method, interface and smoothness diagnostics. It is not affiliated with other display-test websites or brands.

No screenshot, video, file or browsing history is uploaded. Testing and frame analysis occur locally. Only anonymous aggregate test and rating counters are updated, and non-personal interface preferences may be saved on your device.