What is DPI?
DPI stands for Dots Per Inch. It measures how many pixels the cursor moves on screen per inch of physical mouse movement. A mouse set to 800 DPI moves the cursor 800 pixels for every inch you move it.
DPI vs CPI
CPI (Counts Per Inch) is the technically correct term used by mouse manufacturers. DPI became the common marketing term. They refer to the same measurement — how sensitive the mouse sensor is.
DPI Range Guide
- 100–400 DPI — Pro FPS players. Large, precise arm movements.
- 400–800 DPI — Popular FPS range. Balance of control and speed.
- 800–1600 DPI — General gaming, MOBA, everyday use.
- 1600–3200 DPI — RTS games, productivity, high-res monitors.
- 3200+ DPI — Very high-res displays or niche use cases.
Why Actual DPI Differs From Advertised
OS cursor acceleration, Windows Pointer Speed, display scaling, and driver interpolation all affect real cursor travel. Always measure with pointer acceleration disabled for accurate results.
What is eDPI?
Effective DPI (eDPI) = Mouse DPI × In-Game Sensitivity. It normalises different setups into one comparable number so you can compare aim speeds fairly regardless of what hardware or software settings people use.
eDPI Examples
- 800 DPI × 1.5 sens = 1200 eDPI
- 1600 DPI × 0.75 sens = 1200 eDPI (identical feel)
- 400 DPI × 2.0 sens = 800 eDPI
eDPI Ranges for FPS Games
- <400 — Extremely slow. Very rare, niche use.
- 400–800 — Pro-level range. Most top FPS players.
- 800–1200 — Common for competitive players.
- 1200–2000 — Casual / fast-paced games.
- 2000+ — Very fast. Hard to aim precisely at range.
Sensitivity Converter Formula
To match your current feel when changing DPI:
New Sens = (Old DPI × Old Sens) ÷ New DPI
What is 360° Distance?
The physical distance your mouse must travel across the mousepad to complete one full 360° rotation in-game. Lower eDPI = longer distance needed. Most pros use 25–50 cm per 360°.
The Formula
360° Distance (inches) = 360 ÷ (Yaw × Sensitivity × DPI)
Yaw is a game-specific constant — the degrees-per-unit the game rotates per input count.
Game Yaw Values
- CS2 / CS:GO — 0.022°/unit
- Valorant — 0.07°/unit
- Overwatch 2 — 0.0066°/unit
- Apex Legends — 0.022°/unit
- Check your game's config file or wiki for other titles.
Mousepad Size Needed
- <20 cm/360° — Any mousepad. Very fast.
- 20–40 cm/360° — Medium pad (35×30 cm) sufficient.
- 40–60 cm/360° — Large pad recommended (45×40 cm).
- 60+ cm/360° — XL/XXL pad required.
Tips for Accurate Measurements
- Disable pointer acceleration — Windows: Mouse Properties → Pointer Options → uncheck "Enhance pointer precision". macOS: System Settings → Mouse → disable "Natural Scrolling" + acceleration.
- Use a larger distance — 15–20 cm reduces percentage error significantly vs 5 cm.
- Move slowly and steadily — fast flicks introduce more tracking noise.
- Keep movement horizontal — diagonal movement adds path length.
- Take multiple readings — average 5+ measurements for best accuracy.
- Use a hard mousepad — cloth pads can introduce micro-slipping.
Understanding Screen PPI
This tool uses your monitor's PPI (pixels per inch) to calculate physical movement. It auto-detects using a CSS ruler element. If your monitor has a non-standard resolution or scaling, you can override PPI in Settings → Display.
Common Sources of Error
- OS or browser display scaling (125%, 150%) shifts pixel counts
- Mouse acceleration adds inconsistency at different speeds
- Worn or dirty sensor reduces accuracy
- Moving at an angle increases measured pixels
Mouse Sensor Types
- Optical — Uses LED light. Best for hard pads. Most common in gaming mice.
- Laser — Works on more surfaces but can be inconsistent at low speeds.
- Infrared (IR) — Used in older/budget mice. Less precise.
Polling Rate Explained
Polling rate (Hz) is how often your mouse reports its position to the PC per second. Higher = smoother, lower latency:
- 125 Hz — 8ms latency. Basic office mice.
- 500 Hz — 2ms latency. Entry gaming.
- 1000 Hz — 1ms latency. Standard gaming.
- 4000–8000 Hz — Sub-0.25ms. High-end gaming mice.
Mouse Debounce
Debounce delay prevents accidental double-clicks from switch chatter. Office mice: 25–50ms. Gaming mice: 1–10ms. Too low can cause double-click bugs; too high makes fast clicking feel sluggish.
LOD (Lift-Off Distance)
How high you can lift the mouse before tracking stops. Low LOD (0.5–1mm) is preferred for gaming — less unintended cursor drift when repositioning. Adjustable on many gaming mice via software.
Monitor Resolution & DPI
Your monitor's resolution affects how cursor movement feels. A 4K monitor at the same physical size as a 1080p monitor has 4× the pixel density — running the same DPI will feel slower because each pixel is physically smaller.
- 1080p (96 PPI typical) — Standard baseline. Most DPI guides assume this.
- 1440p (108–120 PPI) — Slightly faster feel than 1080p at same DPI.
- 4K (163+ PPI) — Consider higher DPI or lower OS scaling.
Display Scaling & Its Effect
OS display scaling (125%, 150%, 200%) multiplies cursor movement. At 150% scaling, a 800 DPI mouse effectively behaves like 1200 DPI in terms of cursor travel. Always measure DPI with scaling set to 100% for a true hardware reading, or account for it in your calculations.
Refresh Rate & Mouse Feel
Higher monitor refresh rates (144Hz, 240Hz, 360Hz) make mouse movement appear smoother and reduce perceived input lag. Pairing a high-polling-rate mouse (1000–8000Hz) with a high refresh rate monitor is the best setup for competitive gaming.
VSync & Input Lag
VSync synchronises frame output to your monitor but adds 1–2 frames of input lag. For competitive play, disable VSync and use G-Sync or FreeSync instead, which reduce screen tearing without significant lag penalties.
My DPI Seems Too High / Low
1
Check Windows Pointer Speed — it must be at the 6th notch (default) for accurate raw measurement.
2
Disable Enhance Pointer Precision in Windows Mouse Settings before measuring.
3
Check your browser's display scaling — if set to 125%+, pixel counts will be inflated.
4
Override the Screen PPI in Settings → Display if your monitor is non-standard.
Results Are Inconsistent Between Measurements
- Move the mouse slowly and steadily — acceleration and jitter increase variation
- Use a hard mousepad for more consistent sensor tracking
- Ensure the mouse surface is clean — dust/debris cause erratic readings
- Use a longer drag distance (20 cm) to reduce percentage error
The Measure Zone Isn't Responding
- Click Start Measure first before clicking in the zone
- Make sure you're clicking and dragging — not just moving the mouse
- On touch devices, use a single-finger horizontal swipe
- Try refreshing the page if the zone appears stuck
Touch / Mobile Issues
On mobile, the tool uses touch events. For most accurate results on a trackpad or touch screen, use a ruler app alongside the screen and move your finger exactly the target distance. Note: touch tracking is less precise than a hardware mouse.
Is a higher DPI always better?
No. Higher DPI moves the cursor more per inch, making precise aiming harder. Most competitive FPS players prefer 400–1600 DPI with a lower in-game sensitivity. The best DPI is the one that feels consistent for you.
Should I set DPI in mouse software or in-game?
Set DPI in your mouse software (hardware DPI). In-game sensitivity is a software multiplier on top. Changing DPI in-game software without changing hardware DPI doesn't alter the sensor — it just multiplies cursor output. Hardware DPI is always more precise.
Why do pro players use low DPI?
Low DPI forces larger physical movements for the same on-screen distance, giving more granular control. This makes tiny adjustments and flick corrections easier. Combined with low in-game sensitivity, it builds strong muscle memory for consistent aim.
Does DPI affect input lag?
DPI itself doesn't affect input lag — polling rate does. A 1000Hz mouse reports its position every 1ms. DPI only changes how far the cursor moves per count, not how quickly those counts are sent.
What mousepad size do I need?
Use the 360° Rotation Calculator to find your cm/360° value. As a rule: under 30 cm/360° → any pad. 30–50 cm/360° → large pad (45×40 cm). Over 50 cm/360° → XL pad (90×45 cm or larger).
Can I use this tool on mobile?
Yes — the tool supports touch events. Tap "Start Measure", then press and drag horizontally. For accuracy, use a physical ruler alongside the screen and keep the swipe perfectly straight.