If we load a 128 bpm loop into a track that is originally set to 126 bpm, to adjust the loop length to the pattern length we can change the pitch in - 0.3 and it will fit. I couldn’t find a way to adjust it when the difference of bpm is an odd value, I think it is only possible with even values, because we can’t have a - 0.15 pitch for example.
So for each 2bpm difference we change 0.3 pitch.
Hope it helps in some way. And sorry if this subject was already posted.
Unfortunately, that’s only an approximation. It doesn’t work if your starting bpm is a lot different from 128, and it doesn’t work if the bpm difference is much bigger.
This is the kind of repeated calculation that would justify an online calculator … I wonder if somebody has done one already ?
EDIT: Here you go … 2nd calculator on the page works this out for you