What Browser Mouse Polling Rate Tests Actually Measure

A mouse may be configured for 125 Hz, 500 Hz, 1000 Hz, or higher. But when you run a polling rate test in a browser, the displayed number does not come directly from the mouse firmware or raw USB packets.

It represents the timing of mouse movement events that reached the webpage.

That distinction matters when interpreting the result.

How a Browser Test Calculates Observed Hz

A browser-based test listens for mouse movement inside an active testing area. Every accepted movement event has a timestamp.

The basic calculation is:

const intervalMs = currentTime - previousTime;
const observedHz = 1000 / intervalMs;

If two accepted events arrive 1 millisecond apart, the interval-derived result is approximately 1000 events per second.

A 2 millisecond interval produces approximately 500 events per second, while an 8 millisecond interval produces approximately 125 events per second.

The calculation is simple. However, the path an input event follows before reaching the webpage is more complicated.

The Browser Does Not Read Raw USB Reports

A mouse report passes through several stages:

1. The mouse sensor and firmware process movement.
2. The device sends data through USB, Bluetooth, or a wireless receiver.
3. The operating system handles the input.
4. The browser receives an input event.
5. JavaScript processes the event and updates the result.

A browser test observes the event near the end of this path. It does not normally inspect every raw USB HID report generated by the device.

This is why the result should be described as a browser-observed event rate, rather than direct certification of the mouse’s hardware polling rate.

You can run the live mouse polling rate test here:

https://pollingratetester.com/mouse-polling-rate-test/

Why the Displayed Value Changes

Even when the mouse profile remains unchanged, the result can move between attempts.

Several factors affect the event sample:

• Movement speed and distance
• Short pauses during the test
• The pointer leaving the active area
• Browser focus
• Background applications
• Operating-system scheduling
• Browser implementation
• Timer precision
• Wired, Bluetooth, or 2.4 GHz connection mode

The browser may also combine multiple pointer updates into a single dispatched event. This process is known as event coalescing.

Event coalescing can reduce the number of separate events visible to ordinary JavaScript, particularly when input arrives faster than the browser chooses to dispatch it.

Because of these variables, one maximum reading should not be treated as the final answer.

Average and Maximum Values Are Not the Same

The maximum value normally comes from the shortest accepted interval in the sample.

One unusually short interval can create a high peak that the mouse does not sustain.

The average value provides better context, but it can also be reduced by pauses, slow movement, focus changes, and interrupted collection.

For a more useful comparison:

1. Keep the same mouse profile and DPI.
2. Use the same browser.
3. Keep the browser tab active.
4. Move the mouse continuously in controlled circles.
5. Use the same test duration.
6. Run at least three attempts.
7. Compare the average pattern before considering the maximum.

This method does not remove every browser limitation, but it reduces unnecessary variation between attempts.

What a Browser Test Is Useful For

A browser polling rate test is useful when comparing conditions on the same system.

For example, you can compare:

• 500 Hz and 1000 Hz profiles
• Wired and wireless modes
• A receiver connected through a hub and directly to the computer
• Results before and after closing heavy background applications
• Repeated attempts using the same browser and movement pattern

The test can show whether browser-observed event timing changes between controlled setups.

Run the test and compare repeated attempts:

https://pollingratetester.com/mouse-polling-rate-test/

What the Result Cannot Prove

A browser result cannot independently prove that:

• Every raw USB report reached the operating system
• A mouse sustained its advertised hardware polling rate
• A USB port or wireless receiver is faulty
• A high maximum value was maintained throughout the test
• The complete input-to-display latency is low
• A 4000 Hz or 8000 Hz profile was formally validated

Lower-level USB or HID analysis is more suitable when raw hardware verification is required.

Why the Testing Methodology Is Public

Browser tools should clearly explain what they measure and where their limits are.

A large number without measurement context can easily be misunderstood. For that reason, I published the complete testing procedure, calculation references, known limitations, and sample CSV structures in a public GitHub repository.

Review the full methodology on GitHub:

https://github.com/Umairaalam/polling-rate-tester

The repository contains:

• The controlled testing procedure
• Reference calculations
• Known browser limitations
• Mouse and keyboard sample CSV files
• A data dictionary
• Citation information

Permanent Zenodo Archive

The methodology package is also preserved on Zenodo with a permanent Digital Object Identifier.

View the archived release:

https://doi.org/10.5281/zenodo.21533776

The Zenodo record provides a stable citation for the methodology, sample data structure, and documented limitations.

The goal is not to make browser testing sound more precise than it is. The goal is to make the result useful by explaining exactly what the browser observed.