Mouse DPI analyzer

Estimate effective mouse sensitivity from a distance you measure with a physical ruler and movement the browser reports in CSS pixels.

Local session · no device permission

How to use

Mark a straight 5–20 cm (2–8 in) path beside your mouse with a real ruler. Enter the exact travel and choose the matching axis.

Align the mouse at the first mark, select Start run, then move once to the second mark without lifting, reversing or rotating.

Save 3–5 careful trials and compare the median and spread. Repeat at a different speed to expose possible acceleration or inconsistent technique.

1. Set measured travel

Physical travel Unit

Accepted range: 0.5–40 inches equivalent. Longer, carefully measured travel reduces placement error.

Movement axis Use Pointer Lock when available Useful only to avoid screen edges. Start requests temporary capture; Space saves and exits, while Esc exits without saving. It does not make the data raw hardware counts.

Checking browser context…Keep browser zoom, display scaling, pointer speed and acceleration unchanged across trials. These values are not used as correction factors.Rejected contacts: Touch 0 · Pen 0 · Other 0

Ready. Enter a measured distance, align the mouse, then start a run.

2. Record one pass

Idle

Waiting for a run With lock enabled, movement begins after Start captures the pointer. Fallback mode asks you to press, drag and release inside this surface.

Net X 0 CSS px

Net Y 0 CSS px

Move events 0

Pointer Lock hides the cursor until Space, Finish, or the browser’s Escape action exits. If lock is off or denied, keep the pointer inside the dashed surface; crossing its boundary cancels the pass.

3. Repeatability summary

Formula: selected-axis browser movement in CSS px ÷ measured physical inches = effective DPI estimate. Complete a trial to see its arithmetic.

Median estimate —

Mean —

Range —

Spread —

Horizontal median —

Vertical median —

Add at least 3 trials. Runs more than 12% from the current median are marked for review, not automatically removed or diagnosed.

Saved trials

0 / 12

No saved trials yet. A canceled or zero-movement pass is never added.

Estimate, not sensor calibration

Browsers do not expose configured sensor DPI/CPI or raw device counts here. This tool divides browser-reported CSS-pixel movement by your measured travel. It cannot certify, calibrate or diagnose the mouse.

Scaling and acceleration matter

OS pointer speed, acceleration, driver profiles, browser zoom, display scaling, remote desktop and browser behavior can change the estimate. Compare trials only under unchanged settings; speed-dependent results suggest checking acceleration and technique.

Input-source boundary

Touch and pen contacts are rejected. A browser can report mouse-class movement from a physical mouse, trackpad, accessibility tool or remapped input, so a saved run is not proof that a particular mouse produced it.

Private and temporary

No device permission is used, and trial data is not sent or stored by the tool. Up to 12 trials live only in this page session; public-page usage analytics is described in the Privacy Policy. Optional Pointer Lock is requested by Start solely to prevent edge clipping and is released on finish, cancel, loss, page exit or removal.