This tool is expected to come with the new plot shrinker.
Fill in the size of your drive and select what k-size plots you want to fill it with. Are you combining space over multiple disks through raid0 (not recommended)? Just add up the total space over your drives.
A commonly heard myth goes along these lines:
“The additional space used up by a k33 beyond 2x k32 does not contribute to winning a block, so using larger k sizes to fill a hard drive “more” is actually wasting space” – FALSE
With this we can conclude that the number of proofs (N) are directly proportional to the plot size in bytes. K is just a constant that goes into determining the final plot size, and can therefore not simply be misconstrued as a measure for number of proofs.