How to use: Mouse DPI Analyzer
Mark a straight 10–20 cm distance and enter it exactly.
Start a run, lock the pointer and move the mouse from one mark to the other without lifting.
Repeat at least three times; use the median and spread, then compare with vendor settings.
What the result actually measures
The analyzer accumulates browser movement counts while pointer lock is active and divides the observed distance by a user-measured physical travel. Multiple runs produce a median estimate, range and variation percentage.
Measurement boundary: Operating-system pointer scaling, browser behavior, device pixel ratio, acceleration and imperfect desk measurement can affect the estimate. Raw hardware counts are not guaranteed in every environment.
How to interpret the output
Median estimate
The middle run resists one accidental overshoot better than selecting the cleanest-looking result.
Variation
A large run-to-run spread usually means the physical procedure or software path is not repeatable enough.
Observed counts
Movement delivered by the browser; it may differ from raw sensor counts.
Troubleshooting unexpected results
Estimate is far from the label
Check pointer acceleration/scaling, browser zoom, device pixel ratio and the physical measurement before concluding the mouse is off-spec.
Pointer lock is denied
Click the test control from a focused top-level page and allow pointer lock; some embedded or restricted browsers block it.
Frequently asked questions
Is this a raw DPI certificate?
No. It is a transparent browser-observed estimate with repeatability statistics.
Why use a longer distance?
A one-millimeter measuring error becomes a smaller percentage of a longer run.
Does browser zoom matter?
It can affect some delivered coordinate paths, so keep zoom at 100% and record the environment.