| -help | Print out a usage message. |
| -digest | Specifies name of a supported digest to be used. See option -list below : |
| -list | Prints out a list of supported message digests. |
| -c | Print out the digest in two digit groups separated by colons, only relevant if the -hex option is given as well. |
| -d-debug | Print out BIO debugging information. |
| -hex | Digest is to be output as a hex dump. This is the default case for a "normal" digest as opposed to a digital signature. See NOTES below for digital signatures using -hex. |
| -binary | Output the digest or signature in binary form. |
| -xoflenlength | For OpenSSL providers it is required to set this value for shake algorithms, since the previous default values were only set to supply half of the maximum security strength. To ensure the maximum security strength of 128 bits, the xoflen for shake128 should be set to at least 32 (bytes). For compatibility with previous versions of OpenSSL, it may be set to 16, resulting in a security strength of only 64 bits. To ensure the maximum security strength of 256 bits, the xoflen for shake256 should be set to at least 64 (bytes). For compatibility with previous versions of OpenSSL, it may be set to 32, resulting in a security strength of only 128 bits. |
| -r | Output the digest in the "coreutils" format, including newlines. Used by programs like sha1sum(1). |
| -outfilename | Filename to output to, or standard output by default. |
| -signfilename|uri | Note that for algorithms that only support one-shot signing (such as Ed25519, ED448, ML-DSA-44, ML-DSA-65 andML-DSA-87) the digest must not be set. For these algorithms the input is buffered (and not digested) before signing. For these algorithms, if the input is larger than 16MB an error will occur. |
| -keyformDER|PEM|P12|ENGINE | The format of the key to sign with; unspecified by default. See openssl-format-options(1) for details. |
| -sigoptnm:v | Pass options to the signature algorithm during sign or verify operations. Names and values of these options are algorithm-specific and documented in "Signature parameters" in provider-signature(7). |
| -passinarg | The private key password source. For more information about the format of arg see openssl-passphrase-options(1). |
| -verifyfilename | Verify the signature using the public key in "filename". The output is either "Verified OK" or "Verification Failure". |
| -prverifyfilename | Verify the signature using the private key in "filename". |
| -signaturefilename | The actual signature to verify. |
| -hmackey | The openssl-mac(1) command should be preferred to using this command line option. |
| -macalg | The openssl-mac(1) command should be preferred to using this command line option. |
| -macoptnm:v | Passes options to MAC algorithm, specified by -mac key. Following options are supported by both by HMAC and gost-mac: |
| key:string | Specifies MAC key as alphanumeric string (use if key contain printable characters only). String length must conform to any restrictions of the MAC algorithm for example exactly 32 chars for gost-mac. |
| hexkey:string | Specifies MAC key in hexadecimal form (two hex digits per byte). Key length must conform to any restrictions of the MAC algorithm for example exactly 32 chars for gost-mac. |
| -fips-fingerprint | Compute HMAC using a specific key for certain OpenSSL-FIPS operations. |
| -randfiles-writerandfile | See "Random State Options" in openssl(1) for details. |
| -engineid | The engine is not used for digests unless the -engine_impl option is used or it is configured to do so, see "Engine Configuration Module" in config(5). |
| -engine_implid | When used with the -engine option, it specifies to also use engine id for digest operations. |
| -propquerypropq | See "Provider Options" in openssl(1), provider(7), and property(7). |
| file ... | File or files to digest. If no files are specified then standard input is used. |
NAME
openssl-dgst - perform digest operations
SYNOPSIS
openssldgst|digest [-digest] [-list] [-help] [-c] [-d] [-debug] [-hex] [-binary] [-xoflenlength] [-r] [-outfilename] [-signfilename|uri] [-keyformDER|PEM|P12|ENGINE] [-passinarg] [-verifyfilename] [-prverifyfilename] [-signaturefilename] [-sigoptnm:v] [-hmackey] [-macalg] [-macoptnm:v] [-fips-fingerprint] [-engineid] [-engine_implid] [-randfiles] [-writerandfile] [-providername] [-provider-pathpath] [-provparam[name:]key=value] [-propquerypropq] [file ...]
DESCRIPTION
This command output the message digest of a supplied file or files in hexadecimal, and also generates and verifies digital signatures using message digests.
The generic name, openssl dgst, may be used with an option specifying the algorithm to be used. The default digest is sha256. A supported digest name may also be used as the sub-command name. To see the list of supported algorithms, use "openssl list -digest-algorithms"
OPTIONS
- -help
Print out a usage message.
- -digest
Specifies name of a supported digest to be used. See option -list below :
- -list
Prints out a list of supported message digests.
- -c
Print out the digest in two digit groups separated by colons, only relevant if the -hex option is given as well.
- -d, -debug
Print out BIO debugging information.
- -hex
Digest is to be output as a hex dump. This is the default case for a "normal" digest as opposed to a digital signature. See NOTES below for digital signatures using -hex.
- -binary
Output the digest or signature in binary form.
- -xoflenlength
For OpenSSL providers it is required to set this value for shake algorithms, since the previous default values were only set to supply half of the maximum security strength.
To ensure the maximum security strength of 128 bits, the xoflen for shake128 should be set to at least 32 (bytes). For compatibility with previous versions of OpenSSL, it may be set to 16, resulting in a security strength of only 64 bits.
To ensure the maximum security strength of 256 bits, the xoflen for shake256 should be set to at least 64 (bytes). For compatibility with previous versions of OpenSSL, it may be set to 32, resulting in a security strength of only 128 bits.
- -r
Output the digest in the "coreutils" format, including newlines. Used by programs like sha1sum(1).
- -outfilename
Filename to output to, or standard output by default.
- -signfilename|uri
Note that for algorithms that only support one-shot signing (such as Ed25519, ED448, ML-DSA-44, ML-DSA-65 andML-DSA-87) the digest must not be set. For these algorithms the input is buffered (and not digested) before signing. For these algorithms, if the input is larger than 16MB an error will occur.
- -keyformDER|PEM|P12|ENGINE
The format of the key to sign with; unspecified by default. See openssl-format-options(1) for details.
- -sigoptnm:v
Pass options to the signature algorithm during sign or verify operations. Names and values of these options are algorithm-specific and documented in "Signature parameters" in provider-signature(7).
- -passinarg
The private key password source. For more information about the format of arg see openssl-passphrase-options(1).
- -verifyfilename
Verify the signature using the public key in "filename". The output is either "Verified OK" or "Verification Failure".
- -prverifyfilename
Verify the signature using the private key in "filename".
- -signaturefilename
The actual signature to verify.
- -hmackey
The openssl-mac(1) command should be preferred to using this command line option.
- -macalg
The openssl-mac(1) command should be preferred to using this command line option.
- -macoptnm:v
Passes options to MAC algorithm, specified by -mac key. Following options are supported by both by HMAC and gost-mac:
- key:string
Specifies MAC key as alphanumeric string (use if key contain printable characters only). String length must conform to any restrictions of the MAC algorithm for example exactly 32 chars for gost-mac.
- hexkey:string
Specifies MAC key in hexadecimal form (two hex digits per byte). Key length must conform to any restrictions of the MAC algorithm for example exactly 32 chars for gost-mac.
The openssl-mac(1) command should be preferred to using this command line option.
- -fips-fingerprint
Compute HMAC using a specific key for certain OpenSSL-FIPS operations.
- -randfiles, -writerandfile
See "Random State Options" in openssl(1) for details.
- -engineid
The engine is not used for digests unless the -engine_impl option is used or it is configured to do so, see "Engine Configuration Module" in config(5).
- -engine_implid
When used with the -engine option, it specifies to also use engine id for digest operations.
- -providername
- -provider-pathpath
- -provparam[name:]key=value
- -propquerypropq
See "Provider Options" in openssl(1), provider(7), and property(7).
- file ...
File or files to digest. If no files are specified then standard input is used.
EXAMPLES
To create a hex-encoded message digest of a file:
openssl dgst -md5 -hex file.txt
or
openssl md5 file.txtTo sign a file using SHA-256 with binary file output:
openssl dgst -sha256 -sign privatekey.pem -out signature.sign file.txt
or
openssl sha256 -sign privatekey.pem -out signature.sign file.txtTo verify a signature:
openssl dgst -sha256 -verify publickey.pem \
-signature signature.sign \
file.txtNOTES
The digest mechanisms that are available will depend on the options used when building OpenSSL. The "openssl list -digest-algorithms" command can be used to list them.
New or agile applications should use probably use SHA-256. Other digests, particularly SHA-1 and MD5, are still widely used for interoperating with existing formats and protocols.
When signing a file, this command will automatically determine the algorithm (RSA, ECC, etc) to use for signing based on the private key's ASN.1 info. When verifying signatures, it only handles the RSA, DSA, or ECDSA signature itself, not the related data to identify the signer and algorithm used in formats such as x.509, CMS, and S/MIME.
A source of random numbers is required for certain signing algorithms, in particular ECDSA and DSA.
The signing and verify options should only be used if a single file is being signed or verified.
Hex signatures cannot be verified using openssl. Instead, use "xxd -r" or similar program to transform the hex signature into a binary signature prior to verification.
The openssl-mac(1) command is preferred over the -hmac, -mac and -macopt command line options.
SEE ALSO
openssl-mac(1)
HISTORY
The default digest was changed from MD5 to SHA256 in OpenSSL 1.1.0. The FIPS-related options were removed in OpenSSL 1.1.0.
The -engine and -engine_impl options were deprecated in OpenSSL 3.0.
COPYRIGHT
Copyright 2000-2025 The OpenSSL Project Authors. All Rights Reserved.
Licensed under the Apache License 2.0 (the "License"). You may not use this file except in compliance with the License. You can obtain a copy in the file LICENSE in the source distribution or at <https://www.openssl.org/source/license.html>.