# shasum > Calculate or check cryptographic SHA checksums. - Calculate the SHA1 checksum for a file: `shasum {{filename}}` - Calculate the SHA256 checksum for a file: `shasum --algorithm 256 {{filename}}` - Calculate the SHA512 checksum for multiple files: `shasum --algorithm 512 {{filename1}} {{filename2}}` - Check a file with a list of sums against the directory's files: `shasum --check {{list_file}}` - Calculate the SHA1 checksum from stdin: `{{somecommand}} | shasum`