I made an offset wizard that minimizes systemic measurement error if the touch/input polling rate of a player's smartphone or tablet is 30, 50, 60, 90, 120, or 144 Hz and their multiples. These are the most common input polling rates on mobile devices; please check your devices' technical specifications if you have doubts it applies to your device.

How to use it?

1. Play any difficulty.
2. Write down ATE and STE shown on the results screen.
3. Calculate the calibration_accuracy with this formula: calibration_accuracy = STE / √40. If calibration_accuracy ≤ |ATE|, then add ATE to the base note offset in the settings; otherwise you're all set.

Tips:

• Do not try to sync your taps visually — this will only worsen the wizard's ability to set the base note offset correctly.
• First four beats are intended to be skipped.

Examples

Example A

base_note_offset = 0

1. Play the "80 BPM" difficulty.
2. ATE = 0.123, STE = 0.021.
3. calibration_accuracy = 0.021 / √40 ≈ 0.003320. Since calibration_accuracy < |ATE|, add ATE to the base note offset in the settings: new_base_note_offset = 0 + 0.123 = 0.123.

Example B

base_note_offset = 0.456

1. Play the "80 BPM" difficulty.
2. ATE = -0.234, STE = 0.019.
3. calibration_accuracy = 0.019 / √40 ≈ 0.003004. Since calibration_accuracy < |ATE|, add ATE to the base note offset in the settings: new_base_note_offset = 0.456 + (-0.234) = 0.222.

Example C

base_note_offset = 0.09

1. Play the "160 BPM" difficulty.
2. ATE = -0.002, STE = 0.014.
3. calibration_accuracy = 0.014 / √40 ≈ 0.002214. Since calibration_accuracy > |ATE|, you're all set.

Special case: judgement offset

If you use a judgement offset, note that this wizard can't adjust it. All it can adjust is the sum of judgement_offset + base_note_offset. Therefore, if you want to keep your current judgement offset, first set the judgement offset to 0, run the wizard as described above, then subtract your original judgement offset from the resulting base note offset and restore the judgement offset to your preferred value.