Mouse DPI Analyzer — Measure Your Real DPI
Set the DPI your mouse software claims, move the mouse a measured distance along a ruler, and this tells you what it actually delivered. The cursor is captured with Pointer Lock so it cannot run off the screen mid-stroke, and X and Y are measured independently. It is honest about what it can see: the browser only knows how many pixels the cursor moved, so what comes out is effective DPI — sensor DPI multiplied by whatever the operating system is doing to it.
Use Cases
How to test your mouse DPI
On Windows: Pointer Options, speed at the 6th of 11 notches, "Enhance pointer precision" unchecked. Set browser zoom to 100%. Without this you are measuring your pointer settings, not the sensor.
Take the DPI from your mouse software. Pick a distance you can measure on the mousepad — 4 to 6 inches is the useful range, because a short stroke is dominated by where you started and stopped.
The cursor is captured so it keeps counting past the edge of the screen. Lay a ruler beside the mousepad, move in one steady stroke along the axis you picked, then press Esc to record the run.
Run it three to five times. The average is the number to trust — a single pass lands 2–5% off on hand movement alone, which is why the tool keeps your last five runs instead of overwriting.
Frequently Asked Questions
- How accurate is an online DPI test?
- The arithmetic is exact; the measurement is only as good as your ruler. Expect ±2% from hand movement on a 5-inch stroke, which is why the tool averages runs and refuses to call anything under 2% a finding. Anything past 10% is not sensor error — it is a pointer-speed multiplier.
- Does this measure my hardware DPI?
- It measures effective DPI: sensor DPI × OS pointer speed × any acceleration × page zoom. Those multipliers are 1 on Windows with pointer speed at 6/11 and enhance-precision off, so there the reading is the sensor. On macOS the tracking curve is always applied and a web page cannot switch it off, so a Mac reading is a sensitivity measurement.
- Why measure X and Y separately?
- Some sensors, particularly older optical ones and mice used on a patterned pad, track differently along the two axes. A difference of a couple of percent is just how straight your hand moves; a consistent 10% gap across several runs on both axes is a real fault worth returning the mouse for.
- My measured DPI is nowhere near what I set. What is wrong?
- In order of likelihood: pointer acceleration is still on, browser zoom is not 100%, the distance you moved was not the distance you entered, or the mouse software profile you are looking at is not the one currently active on the device. Rule those three out before suspecting the sensor.
- How do I keep my aim after changing DPI?
- DPI × in-game sensitivity sets your cm/360, so when you double the DPI, halve the sensitivity. The tool shows the matched sensitivity for the nearest standard DPI step once it has a reading.
- Does this need a download or driver access?
- No. It reads the same pointer-movement events any web page receives and does the arithmetic locally. There is nothing to install, no driver access, and nothing is sent to a server.
Private by design. DPI is measured from pointer movement events inside this page — no driver access, no downloads, and nothing is sent to a server.
Related tools
More free, in-browser tools from the More Tools set — every one runs locally, with no sign-up and no upload.