Memory cell level assignment using optimal level permutations in a non-volatile memory

A memory system includes a memory device and a memory controller. The memory device includes a plurality of memory cells. The memory controller is configured to manage the memory device using a cell level assignment with respect to a plurality of memory cell levels, determine a cell count for each of the cell levels associated with original data of the memory device that is to be accessed, predict an error rate from the cell counts, and selectively adjust the cell level assignment based on the error rate.