MD5(1)                      General Commands Manual                     MD5(1)

NAME
     md5, sha1, sha224, sha256, sha384, sha512, md5sum, sha1sum, sha224sum,
     sha256sum, sha384sum, sha512sum – calculate a message-digest fingerprint
     (checksum) for a file

SYNOPSIS
     md5 [-pqrtx] [-c string] [-s string] [file ...]

     md5sum [-bctwz] [--binary] [--check] [--help] [--ignore-missing]
            [--quiet] [--status] [--strict] [--tag] [--text] [--version]
            [--warn] [--zero] [file ...]

            (All other hashes have the same options and usage.)

     shasum [-0bchqstUvw] [--01] [-a | --algorithm alg] [--binary] [--check]
            [--help] [--ignore-missing] [--quiet] [--status] [--strict]
            [--tag] [--text] [--UNIVERSAL] [--version] [--warn] [file ...]

DESCRIPTION
     The md5, sha1, sha224, sha256, sha384, and sha512 utilities take as input
     a message of arbitrary length and produce as output a “fingerprint” or
     “message digest” of the input.

     The md5sum, sha1sum, sha224sum, sha256sum, sha384sum, and sha512sum
     utilities do the same, but with command-line options and an output format
     that match those of their similary named GNU utilities.

     In all cases, each file listed on the command line is processed
     separately.  If no files are listed on the command line, or a file name
     is given as -, input is taken from stdin instead.

     It is conjectured that it is computationally infeasible to produce two
     messages having the same message digest, or to produce any message having
     a given prespecified target message digest.  The SHA-224, SHA-256,
     SHA-384, and SHA-512 algorithms are intended for digital signature
     applications, where a large file must be “compressed” in a secure manner
     before being encrypted with a private (secret) key under a public-key
     cryptosystem such as RSA.

     The MD5 and SHA-1 algorithms have been proven to be vulnerable to
     practical collision attacks and should not be relied upon to produce
     unique outputs, nor should they be used as part of a cryptographic
     signature scheme. As of 2017-03-02, there is no publicly known method to
     reverse either algorithm, i.e., to find an input that produces a specific
     output.

     It is recommended that all new applications use SHA-512 instead of one of
     the other hash functions.

   BSD OPTIONS
     The following options are available in BSD mode, i.e. when the program is
     invoked with a name that does not end in “sum”:

     -c string, --check=string
             Compare the digest of the file against this string.  If combined
             with the -q or --quiet option, the calculated digest is printed
             in addition to the exit status being set.  (Note that this option
             is not yet useful if multiple files are specified.)

     -p, --passthrough
             Echo stdin to stdout and append the checksum to stdout.  In this
             mode, any files specified on the command line are silently
             ignored.

     -q, --quiet
             Quiet mode — only the checksum is printed out.  Overrides the -r
             or --reverse option.

     -r, --reverse
             Reverses the format of the output.  This helps with visual diffs.
             Does nothing when combined with the -ptx options.

     -s string, --string=string
             Print a checksum of the given string.  In this mode, any files
             specified on the command line are silently ignored.

     -t, --time-trial
             Run a built-in time trial.  For the -sum versions, this is a nop
             for compatibility with coreutils.

     -x, --self-test
             Run a built-in test script.

   GNU OPTIONS
     The following options are available in GNU mode, i.e. when the program is
     invoked with a name that ends in “sum”:

     -b, --binary
             Read files in binary mode.

     -c, --check
             The file passed as arguments must contain digest lines generated
             by the same digest algorithm in either classical BSD format or in
             GNU coreutils format.  A line with the file name followed by a
             colon “:” and either OK or FAILED is written for each well-formed
             line in the digest file.  If applicable, the number of failed
             comparisons and the number of lines that were skipped since they
             were not well-formed are printed at the end.  The --quiet option
             can be used to quiesce the output unless there are mismatched
             entries in the digest.

     --help  Print a usage message and exit.

     --ignore-missing
             When verifying checksums, ignore files for which checksums are
             given but which aren't found on disk.

     --quiet
             When verifying checksums, do not print anything unless the
             verification fails.

     --status
             When verifying checksums, do not print anything at all.  The exit
             code will reflect whether verification succeeded.

     --strict
             When verifying checksums, fail if the input is malformed.

     --tag   Produce BSD-style output.

     -t, --text
             Read files in text mode.  This is the default.  Note that this
             implementation does not differentiate between binary and text
             mode.

     --version
             Print version information and exit.

     -w, --warn
             When verifying checksums, warn about malformed input.

     -z, --zero
             Terminate output lines with NUL rather than with newline.

EXIT STATUS
     The md5, sha1, sha224, sha256, sha384, and sha512 utilities exit 0 on
     success, 1 if at least one of the input files could not be read, and 2 if
     at least one file does not have the same hash as the -c option.

     The md5sum, sha1sum, sha224sum, sha256sum, sha384sum, and sha512sum
     utilities exit 0 on success and 1 if at least one of the input files
     could not be read or, when verifying checksums, does not have the
     expected checksum.

EXAMPLES
     Calculate the MD5 checksum of the string “Hello”.

           $ md5 -s Hello
           MD5 ("Hello") = 8b1a9953c4611296a827abf8c47804d7

     Same as above, but note the absence of the newline character in the input
     string:

           $ echo -n Hello | md5
           8b1a9953c4611296a827abf8c47804d7

     Calculate the checksum of multiple files reversing the output:

           $ md5 -r /boot/loader.conf /etc/rc.conf
           ada5f60f23af88ff95b8091d6d67bef6 /boot/loader.conf
           d80bf36c332dc0fdc479366ec3fa44cd /etc/rc.conf

     This is almost but not quite identical to the output from GNU mode:

           $ md5sum /boot/loader.conf /etc/rc.conf
           ada5f60f23af88ff95b8091d6d67bef6  /boot/loader.conf
           d80bf36c332dc0fdc479366ec3fa44cd  /etc/rc.conf

     Note the two spaces between hash and file name.  If binary mode is
     requested, they are instead separated by a space and an asterisk:

           $ md5sum -b /boot/loader.conf /etc/rc.conf
           ada5f60f23af88ff95b8091d6d67bef6 */boot/loader.conf
           d80bf36c332dc0fdc479366ec3fa44cd */etc/rc.conf

     Write the digest for /boot/loader.conf in a file named digest.  Then
     calculate the checksum again and validate it against the checksum string
     extracted from the digest file:

           $ md5 /boot/loader.conf > digest && md5 -c $(cut -f2 -d= digest) /boot/loader.conf
           MD5 (/boot/loader.conf) = ada5f60f23af88ff95b8091d6d67bef6

     Same as above but comparing the digest against an invalid string
     (“randomstring”), which results in a failure.

           $ md5 -c randomstring /boot/loader.conf
           MD5 (/boot/loader.conf) = ada5f60f23af88ff95b8091d6d67bef6 [ Failed ]

     In GNU mode, the -c option does not compare against a hash string passed
     as parameter.  Instead, it expects a digest file, as created under the
     name digest for /boot/loader.conf in the example above.

           $ md5 -c digest /boot/loader.conf
           /boot/loader.conf: OK

     The digest file may contain any number of lines in the format generated
     in either BSD or GNU mode.  If a hash value does not match the file,
     “FAILED” is printed instead of “OK”.

SEE ALSO
     cksum(1), md5(3), sha(3), sha256(3), sha384(3), sha512(3)

     R. Rivest, The MD5 Message-Digest Algorithm, RFC1321.

     J. Burrows, The Secure Hash Standard, FIPS PUB 180-2.

     D. Eastlake and P. Jones, US Secure Hash Algorithm 1, RFC 3174.

     Secure Hash Standard (SHS):
     https://www.nist.gov/publications/secure-hash-standard-shs

ACKNOWLEDGMENTS
     This utility was originally derived from a program which was placed in
     the public domain for free general use by RSA Data Security.

     Support for SHA-1 was added by Oliver Eikemeier <eik@FreeBSD.org>.

     Support for SHA-2 was added by Colin Percival <cperciva@FreeBSD.org> and
     Allan Jude <allanjude@FreeBSD.org>.

     Compatibility with GNU coreutils was added by Warner Losh
     <imp@FreeBSD.org> and much expanded by Dag-Erling Smørgrav
     <des@FreeBSD.org>.

macOS 15.2                     February 13, 2024                    macOS 15.2