Mouse DPI Test
Measure the real DPI (CPI) of your mouse: put a ruler on your desk, hold the left button, move the mouse an exact distance and release. Repeat a few times and the test averages your runs.
| Run | Distance | Counts | DPI | Delete |
|---|---|---|---|---|
| No runs yet. | ||||
Advanced settings
How to use the Mouse DPI Test
- Put a ruler on your desk and set the distance you will move (for example 4 inches or 10 cm).
- Press Start measurement. The cursor is hidden so it cannot stop at the screen edge.
- Line up the mouse with the start of the ruler, hold the left button, move exactly the set distance and release.
- Repeat 3 to 5 times. Each run is listed and averaged; delete any run where you slipped.
- Read your DPI and the nearest standard step, and enter your in-game sensitivity to get your eDPI.
Mouse DPI formula
The test counts how far the sensor reports the mouse moved and divides by how far it really moved:
DPI = counts ÷ distance in inches, and with centimetres DPI = counts ÷ (cm ÷ 2.54).
Example: you move the mouse 10 cm (3.94 inches) and the browser receives 3,150 counts. 3,150 ÷ 3.94 = 800 DPI. The test measures the straight-line distance between where you pressed and where you released, so a slight angle against the ruler does not matter, but curving or moving back and forth does.
Expected counts for common DPI settings
| DPI | Counts for 2 in (5.08 cm) | Counts for 4 in (10.16 cm) | Counts for 10 cm |
|---|---|---|---|
| 400 | 800 | 1,600 | 1,575 |
| 800 | 1,600 | 3,200 | 3,150 |
| 1,600 | 3,200 | 6,400 | 6,299 |
| 3,200 | 6,400 | 12,800 | 12,598 |
| 6,400 | 12,800 | 25,600 | 25,197 |
Tips for an accurate measurement
- Use a longer distance. A 1 mm reading error is 2% of 5 cm but only 0.5% of 20 cm.
- Line up a fixed point such as the front edge of the mouse with the ruler marks, both at the start and the end.
- Move slowly and steadily in one straight line, and do not lift the mouse.
- Turn off acceleration if raw input is not available: on Windows set pointer speed to the middle (6 of 11) and untick Enhance pointer precision. Mouse software with "angle snapping" or smoothing can also change counts.
- Average 3 to 5 runs and delete any run where the mouse slipped.
Frequently asked questions
How does the mouse DPI test work?
DPI (more precisely CPI, counts per inch) is how many movement counts the mouse sensor reports per inch travelled. The test adds up all the movement the browser receives while you hold the button, then divides by the physical distance: DPI = counts ÷ inches. With centimetres it first converts: inches = cm ÷ 2.54.
Why is my measured DPI different from the box or software setting?
Sensors are rarely exact; a 5 to 10% difference from the advertised value is common. Measuring errors also matter: a ruler misread by 2 mm on a 10 cm move is a 2% error. Use a longer distance, move in a straight line and average several runs for the best result.
What is raw input and why does it matter?
Operating systems can change mouse movement with pointer speed and acceleration (Enhance pointer precision on Windows). Where the browser supports it, the test asks for unadjusted movement, which gives the sensor's counts directly. If raw input is not available, set Windows pointer speed to the default (6 of 11) and turn off Enhance pointer precision, or on macOS expect the result to include the system's acceleration.
Why does it need to hide the cursor?
At 1600 DPI, moving 4 inches is 6400 counts, far wider than most screens. The test uses pointer lock so the movement is counted even past the screen edge. Press Esc at any time to get the cursor back.
What is eDPI?
eDPI (effective DPI) is your mouse DPI multiplied by your in-game sensitivity. It lets players compare overall sensitivity across different DPI settings in the same game: 800 DPI at sensitivity 0.5 and 400 DPI at sensitivity 1.0 both give 400 eDPI.
What DPI should I use?
There is no single best value. Many competitive players use 400 to 1600 DPI with a low in-game sensitivity, while 1600 to 3200 DPI suits high resolution desktop screens. Pick a DPI that lets you move across your screen comfortably, then fine tune with sensitivity.
Does this work with a touchpad or touch screen?
It is designed for a mouse. Touchpads use acceleration and different units, so the result is not a meaningful DPI. On phones and tablets there is no mouse sensor to measure.