Abstract: A computer-implemented method for efficient backup deduplication may include (1) identifying a file to be divided into chunks for deduplication, (2) requesting, from a server, a chunk size to use when dividing the file for deduplication by submitting at least one attribute of the file to the server, the server selecting the chunk size based at least in part on a projected chunk reuse rate when the file is deduplicated according to the chunk size, (3) receiving from the server, in response to requesting the chunk size, the chunk size to use when dividing the file for deduplication, and (4) dividing the file for deduplication into a plurality of chunks according to the chunk size. Various other methods, systems, and computer-readable media are also disclosed.