How to get the MD5 checksum for a file: md5sum, digest, csum, fciv

LINUX: md5sum fileName

In Linux, the md5sum utility can be used:
aemtux1:/ % md5sum binary.file
0c4627e70d168f7f78257e6dd01fdb60 binary.file

This utility is provided by the following rpm package (the package name
is the key element, because the version number depends on your Linux
installation)
% rpm -qf /usr/bin/md5sum
coreutils-5.2.1-23.13

AIX: csum -h MD5 fileName

In AIX, there is no native "md5sum" but the MD5 hash function is
provided by csum (provided and supported in AIX 5.3 and later):
csum -h MD5

aemaix1:/ % csum -h MD5 binary.file
0c4627e70d168f7f78257e6dd01fdb60 binary.file

Note: You may need to apply fixes to AIX for csum to handle files larger than 2 GB. For example:
IV03170: csum to support files more than 2GB APPLIES TO AIX 6100-07

Solaris: digest -a md5 -v fileName

In Solaris there is no native "md5sum", but "digest" can be used:

aemsun4:/ % digest -a md5 -v binary.file
md5 (binary.file) = 0c4627e70d168f7f78257e6dd01fdb60

HP-UX: md5sum fileName

HP-UX MD5 Secure Checksum
Product details & specifications
Overview
The HP-UX MD5 Secure Checksum A.01.01.02 bundle (bundle name
MD5Checksum) provides a file integrity utility and API based on the
standard Message Digest 5 (MD5) algorithm. The MD5Checksum bundle
consists of the following two components that can be installed
independently:
- HP-UX MD5sum (md5sum checksum command)
- HP-UX LibCryptX (libcryptx libraries providing MD5 APIs)
The md5sum command is based on the MD5 algorithm and generates 128-bit
message digests. The md5sum command enables you to verify the integrity
of files downloaded over a network connection. You can also use the
md5sum command to compare files and verify the integrity of files.

HP NonStop Server (NSS): md5sum fileName

In HP NonStop Server, the md5sum command is available in OSS.

Windows: md5sum fileName
fciv -md5 fileName

Microsoft does not offer a supported tool for generating the MD5 hash.

There are 2 choices:

a) The md5sum utility can be found within the following package of
useful utilities that were developed to mimic their corresponding peer
in Unix. The UnxUtils.zip and UnxUpdates.zip packages contain such
utilities. For details on the utilities that are provided in these
packages and download links see:

GNU utilities for Win32

Example run:
H:\> md5sum binary.file
0c4627e70d168f7f78257e6dd01fdb60 *binary.file

b) Microsoft offers a NON-supported utility called "fciv":

Availability and description of the File Checksum Integrity Verifier utility
The File Checksum Integrity Verifier (FCIV) is a command-prompt utility
that computes and verifies cryptographic hash values of files. FCIV can
compute MD5 or SHA-1 cryptographic hash values. These values can be
displayed on the screen or saved in an XML file database for later use
and verification.

Example run:
H:\62570,379,000\2011-01-21> fciv -md5 binary.file
//
// File Checksum Integrity Verifier version 2.05.
//
0c4627e70d168f7f78257e6dd01fdb60 binary.file

Caveat:
During the writing of this technote, we found that the fciv utility
worked fine in some Windows systems but failed in other systems with the
following error. We could not find a way to overcome it. Thus, use this
unsupported tool at your own risk.
Error during CryptAcquireContext.
Error msg : An internal error occurred.

Related information