NAME
cksum - compute and verify file checksums
SYNOPSIS
cksum [OPTION]... [FILE]...
DESCRIPTION
Print or verify checksums. By default use the 32 bit CRC algorithm.
With no FILE, or when FILE is -, read standard input.
Mandatory arguments to long options are mandatory for short options too.
- -a, --algorithm=TYPE
-
select the digest type to use. See DIGEST below
- --base64
-
emit base64-encoded digests, not hexadecimal
- -c, --check
-
read checksums from the FILEs and check them
- -l, --length=BITS
-
digest length in bits; must not exceed the max size and must be a multiple of 8 for blake2b; must be 224, 256, 384, or 512 for sha2 or sha3
- --raw
-
emit a raw binary digest, not hexadecimal
- --tag
-
create a BSD-style checksum (the default)
- --untagged
-
create a reversed style checksum, without digest type
- -z, --zero
-
end each output line with NUL, not newline, and disable file name escaping
The following five options are useful only when verifying checksums:
- --ignore-missing
-
don't fail or report status for missing files
- --quiet
-
don't print OK for each successfully verified file
- --status
-
don't output anything, status code shows success
- --strict
-
exit non-zero for improperly formatted checksum lines
- -w, --warn
-
warn about improperly formatted checksum lines
- --debug
-
indicate which implementation used
- --help
-
display this help and exit
- --version
-
output version information and exit
DIGEST determines the digest algorithm and default output format:
- sysv
-
(equivalent to sum -s)
- bsd
-
(equivalent to sum -r)
- crc
-
(equivalent to cksum)
- crc32b
-
(only available through cksum)
- md5
-
(equivalent to md5sum)
- sha1
-
(equivalent to sha1sum)
- sha2
-
(equivalent to sha{224,256,384,512}sum)
- sha3
-
(only available through cksum)
- blake2b
-
(equivalent to b2sum)
- sm3
-
(only available through cksum)
When checking, the input should be a former output of this program, or equivalent standalone program.
AUTHOR
Written by Padraig Brady and Q. Frank Xia.
REPORTING BUGS
Report bugs to: <[email protected]>.
Report any translation bugs to: <https://translationproject.org/team/>.
GNU coreutils home page: <https://www.gnu.org/software/coreutils/>
General help using GNU software: <https://www.gnu.org/gethelp/>
COPYRIGHT
Copyright © 2026 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>.
This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law.
SEE ALSO
Full documentation <https://www.gnu.org/software/coreutils/cksum>
or available locally via: info '(coreutils) cksum invocation'