PSA Method
How PSA calculates your sensitivity: all 7 rounds explained
A result should be something you can check. Here is the arithmetic used by this website, what your choices change, and what the final number cannot tell you.
PSA Method · Implementation guide · Updated October 26, 2026
The rule behind each choice
Enter your in-game sensitivity, not your mouse DPI or eDPI. For each round, this calculator multiplies the current base by a lower factor and a higher factor. You test those two candidates in your game. The next base is the midpoint between the current base and the candidate you selected.
For example, with a base of 1.00, the first candidates are 0.50 and 1.50. Choosing Lower produces a next base of (1.00 + 0.50) ÷ 2 = 0.75. Choosing Higher instead produces 1.25. The selected candidate is therefore not itself the next base. The same midpoint rule runs after the seventh choice to produce the final result.
These are the rules of this website’s implementation. They describe a preference-based search, not a scientifically validated test of aiming skill. Other calculators may use different schedules or rounding rules.
candidate = base × factor; next base = (base + chosen candidate) ÷ 2
| Round | Lower factor | Higher factor |
|---|---|---|
| 1 | 0.5 | 1.5 |
| 2 | 0.5 | 1.5 |
| 3 | 0.6 | 1.4 |
| 4 | 0.7 | 1.3 |
| 5 | 0.8 | 1.2 |
| 6 | 0.9 | 1.1 |
| 7 | 0.95 | 1.05 |
A complete worked example
Start: 1.00. Choices: Lower, Higher, Higher, Lower, Higher, Higher, Lower. This is an arithmetic demonstration, not a player test or a recommended sequence.
| Round | Current base | Lower | Higher | Choice | Next base |
|---|---|---|---|---|---|
| 1 | 1.00 | 0.50 | 1.50 | Lower | 0.75 |
| 2 | 0.75 | 0.375 | 1.13 | Higher | 0.938 |
| 3 | 0.938 | 0.563 | 1.31 | Higher | 1.13 |
| 4 | 1.13 | 0.787 | 1.46 | Lower | 0.956 |
| 5 | 0.956 | 0.765 | 1.15 | Higher | 1.05 |
| 6 | 1.05 | 0.947 | 1.16 | Higher | 1.10 |
| 7 | 1.10 | 1.05 | 1.16 | Lower | 1.08 |
This example produces ≈ 1.07685703125 internally; the calculator displays 1.08. Different choices produce different results. The table uses the same adaptive precision as the tool.
Display precision and very small values
Values show at least two decimal places, with extra places for values below 1 to retain at least three significant digits. For example, 0.9375 is shown as 0.938, but the next round still starts from 0.9375. Intermediate calculations use JavaScript number precision; recalculating with only the displayed numbers can therefore differ slightly from the tool.
Small positive sensitivities keep enough digits to avoid displaying 0.00: for example, 0.003188615625 displays as 0.00319. Your game may accept fewer decimal places. If both candidates become the same setting in-game, further comparison cannot distinguish them. The downloaded record includes displayed and internal values so you can check both.
Copy result copies the displayed value. Retest from result uses the internal value. If you manually enter the rounded result instead, you are starting a slightly different run. Record the value your game actually accepts; extra digits are not evidence of a better personal setting.
Why your starting value matters
For the same sequence of choices, the output scales with the starting sensitivity. Starting at 2.00 gives twice the internal result of starting at 1.00. The calculator does not observe your mouse movement and cannot correct an unsuitable starting point by itself.
With this seven-round schedule, choosing Lower every time ends at about 0.318862 × the starting value. Choosing Higher every time ends at about 2.552730 × the starting value. These are arithmetic limits, not suggested sensitivity ranges. If both candidates are consistently unmanageable, stop and establish a usable in-game baseline instead of forcing seven choices.
Keep DPI fixed during one run. When changing DPI within the same game and aiming mode, a starting conversion is new sensitivity = old sensitivity × old DPI ÷ new DPI. For example, 1.20 at 800 DPI corresponds to 0.60 at 1600 DPI by this calculation. Verify the physical turn in-game; equal eDPI is not a conversion rule between different games.
Keep a record and compare fairly
After seven choices, use Download test record beside the result. The text file contains the starting value, all seven choices, displayed and internal candidates, and the final value. It is generated in your browser when you press the button. The export adds no upload request; the site’s separate analytics choices are described in the privacy policy.
Add your game, DPI, aiming mode, practice task, duration and observations to the blank fields in the file. The calculator cannot fill these in because it does not measure your game. Keep the original setting as a comparison and give each candidate the same task and time. Swap the testing order on a repeat comparison.
Undo removes the last choice; completing that round again updates the export. Refreshing or switching language in the same tab restores the saved run when session storage is available. Download before closing the tab if you want a durable record. Reset or editing the starting value begins a new run.
What this method does not measure
Seven decisions do not establish statistical confidence, a professional benchmark or a guaranteed improvement. The result reflects your choices and the fixed arithmetic above. Fatigue, warm-up, practice order and an inconsistent drill can change those choices.
If the new setting feels worse, compare it with your original setup under the same conditions. Record a specific problem such as overshooting small targets or running out of mouse space. Use the troubleshooting guide to decide what to check before another run. Stop when further comparisons no longer tell you anything useful.