Mouse DPI Test
Find your mouse's actual DPI without any software. Drag your mouse exactly 1 physical inch across a ruler, and this tool calculates your real sensor CPI/DPI from the pixel count your sensor reported. Measured live here — no driver readouts, no manufacturer claims.
- Disable OS pointer acceleration (set pointer speed to 6/11 on Windows, or disable "Enhance Pointer Precision").
- Place a physical ruler beside your mouse pad.
- Click the left zone on the canvas to start measuring.
- Drag exactly 1 inch (or your chosen distance) and click to finish.
- Read your calculated DPI from the result.
"Enhance Pointer Precision" in Windows applies a non-linear curve on top of raw sensor output. With it enabled, your measured DPI will be wrong — it must be disabled before running this test.
What This Test Measures: Sensor CPI Output
DPI (Dots Per Inch) — more accurately called CPI (Counts Per Inch) in hardware engineering — is the number of raw position update counts your mouse sensor generates per physical inch of movement on the surface. A mouse set to 800 DPI sends 800 count updates for every inch it travels. At 1600 DPI, it sends 1600 counts for the same physical distance. Ruler-based measurement isolates sensor resolution, but you can calibrate other aim settings using our full suite of mouse tests.
Your OS turns those counts into cursor pixels using your DPI setting multiplied by your system pointer speed. This test bypasses that layer entirely: we measure the raw pixel delta reported by your browser's Pointer Events API, compare it against the physical distance you moved, and calculate your actual sensor count-per-inch output. The result is your true hardware DPI — not what your software panel reports, but what your sensor is actually outputting, measured directly on this page.
This matters because many mice have DPI values that drift from their labeled setting over time, or were slightly off from the factory. Knowing your real DPI is the foundation of accurate eDPI calculation.
How to Read Your DPI Result
- Within ±5% of your set DPI: Normal sensor accuracy. The small variance comes from imprecise physical ruler measurement — not sensor error.
- 5–10% below labeled DPI: Slight under-reporting. Could be measurement error (physical inch not perfectly precise) or minor sensor calibration drift.
- More than 10% off: Significant discrepancy. Either your mouse DPI switch is on the wrong setting, OS pointer acceleration is still active, or the sensor has hardware issues.
Common DPI settings for context: 400 and 800 DPI are standard for competitive FPS. 1600 DPI is common for office use. 3200+ DPI increases cursor sensitivity but can amplify sensor noise.
What Causes an Inaccurate DPI Reading
- OS pointer acceleration still active: Windows "Enhance Pointer Precision" applies a variable multiplier to sensor counts. Your measured DPI will be inflated or deflated depending on how fast you moved during the test. Disable it completely before testing.
- Imprecise physical measurement: Dragging 0.9 inches instead of 1.0 inch gives a reading 10% off. Use a physical ruler and drag exactly between clear markings.
- DPI step mismatch: If your mouse has a DPI button and you are on the wrong step, your sensor is outputting a different value than you expect. Check your mouse software to confirm the active DPI setting.
- Surface interference: Extremely glossy or transparent surfaces confuse optical sensors, causing count drops or skips. Test on a cloth or hard mouse pad with visible surface texture.
How to Use Your DPI Result
Once you know your real DPI, you can:
- Calculate your accurate eDPI — multiply this verified DPI by your in-game sensitivity for a true effective sensitivity figure.
- Use the Sensitivity Converter to translate this DPI into equivalent sensitivity values across games.
- Identify if your hardware DPI is drifting — if the same mouse measures 780 DPI when set to 800, you may want to calibrate or update firmware.
Want to understand the physical difference between DPI and CPI, and how sensor architecture determines maximum useful DPI? Read our guide on what mouse DPI actually measures — and learn how to choose the best DPI setting for FPS games based on your mousepad size and playstyle.
Use this physical ruler drag test. Disable OS pointer acceleration, then drag exactly 1 inch across a ruler and read the pixel count. The formula is: Measured Pixels ÷ Physical Inches = DPI.
Most commonly because OS pointer acceleration is active — this is the most common cause of inflated readings. The second most common cause is imprecise physical measurement. Ensure your drag distance is exactly 1 inch on a real ruler.
No. Very high DPI (above 1600) amplifies sensor jitter and smoothing artifacts. Most professional FPS players use 400–800 DPI with higher in-game sensitivity, keeping sensor output clean and predictable.