How DPI measurement works.
Understanding mouse DPI, how we measure it, and why our approach delivers accurate results.
What is mouse DPI?
DPI stands for Dots Per Inch. It measures how many pixels your cursor moves on screen for every inch your mouse physically travels on your desk. A mouse set to 800 DPI moves the cursor 800 pixels for every inch of physical movement.
At 800 DPI, moving your mouse 2 inches to the right moves the cursor 1,600 pixels to the right. At 1600 DPI, the same 2-inch movement moves the cursor 3,200 pixels.
DPI vs sensitivity.
DPI is a hardware setting — it's determined by your mouse's sensor. Sensitivity is a software multiplier applied by your operating system or game. They work together:
| Aspect | DPI | Sensitivity |
|---|---|---|
| Type | Hardware (sensor) | Software (OS/game) |
| Resolution | More data points | Multiplies existing data |
| Precision | Higher = more precise | Higher = less precise |
| Quality | Native sensor data | Can cause pixel skipping |
For the best accuracy, use a higher DPI with lower in-game sensitivity rather than a low DPI with high sensitivity. The sensor captures more movement data at higher DPI.
How we measure DPI.
Our tool captures raw mouse movement data directly from your hardware using modern browser technology — bypassing any OS-level processing that could distort the result. Here's the process from your perspective:
Calibrate your screen
Enter your screen's diagonal size so the tool knows how many physical inches correspond to your screen's pixels. This is what makes the measurement real-world accurate.
Set a target distance
Choose how far you'll physically move your mouse — 5 inches is a good starting point. Use the on-screen ruler as your reference guide.
Move and measure
Click the test area to begin, move your mouse the target distance, then click again to finish. The tool processes the raw movement data and calculates your DPI instantly.
Why Pointer Lock API?
Most online DPI testers track cursor position on screen, which has several problems:
- Screen edge clipping: The cursor stops at screen boundaries, losing movement data
- OS acceleration: Most operating systems apply mouse acceleration by default, distorting results
- Sub-pixel rounding: Cursor positions are integers, losing fractional pixel precision
- Window constraints: The test area's size limits how far you can move
The Pointer Lock API bypasses all of these. It reports raw hardware movement deltas — the actual number of units the mouse sensor detected. The cursor is locked and invisible; only the raw data matters.
For the most accurate results, disable mouse acceleration in your OS settings. On Windows: Settings → Mouse → Additional mouse options → uncheck 'Enhance pointer precision.' On macOS, use a tool like LinearMouse or the terminal to disable acceleration.
Common DPI settings.
| DPI | Use Case | Common For |
|---|---|---|
| 400 | Competitive FPS gaming | CS2, Valorant pros |
| 800 | FPS gaming / general use | Most popular DPI |
| 1600 | Balanced gaming / work | High-res displays |
| 3200+ | Design / multi-monitor | 4K+ displays |