You can check that the version of GnuPG that you want to install is original and unmodified by either verifying the file's signature or comparing the checksum with the one published in the release announcement.

If you already have a trusted version of GnuPG installed, you can check the supplied signature. For example, to check the signature of the file gnupg-2.2.41.tar.bz2, you can use this command:

$ gpg --verify gnupg-2.2.41.tar.bz2.sig gnupg-2.2.41.tar.bz2

Note: you should never use a GnuPG version you just downloaded to check the integrity of the source — use an existing, trusted GnuPG installation, e.g., the one provided by your distribution.

If the output of the above command is similar to the following, then either you don't have our distribution keys (our signing keys are here) or the signature was generated by someone else and the file should be treated suspiciously.

gpg: Signature made Fri 09 Oct 2015 05:41:55 PM CEST using RSA key ID 4F25E3B6
gpg: Can't check signature: No public key
gpg: Signature made Tue 13 Oct 2015 10:18:01 AM CEST using RSA key ID 33BD3F06
gpg: Can't check signature: No public key

If you instead see:

gpg: Good signature from "Werner Koch (dist sig)" [unknown]
gpg: WARNING: This key is not certified with a trusted signature!
gpg:          There is no indication that the signature belongs to the owner.
Primary key fingerprint: D869 2123 C406 5DEA 5E0F  3AB5 249B 39D2 4F25 E3B6
gpg: Signature made Tue 13 Oct 2015 10:18:01 AM CEST using RSA key ID 33BD3F06
gpg: Good signature from "NIIBE Yutaka (GnuPG Release Key) <gniibe@fsij.org>" [unknown]
gpg: WARNING: This key is not certified with a trusted signature!
gpg:          There is no indication that the signature belongs to the owner.
Primary key fingerprint: 031E C253 6E58 0D8E A286  A9F2 2071 B08A 33BD 3F06

then you have a copy of our keys and the signatures are valid, but either you have not marked the keys as trusted or the keys are a forgery. In this case, at the very least, you should compare the fingerprints that are shown to those on the signing keys page. Even better is to compare the fingerprints with those shown on our business cards, which we handout at events that we attend.

Ideally, you'll see something like:

gpg: Signature made Fri 09 Oct 2015 05:41:55 PM CEST using RSA key ID 4F25E3B6
gpg: Good signature from "Werner Koch (dist sig)" [full]
gpg: Signature made Tue 13 Oct 2015 10:18:01 AM CEST using RSA key ID 33BD3F06
gpg: Good signature from "NIIBE Yutaka (GnuPG Release Key) <gniibe@fsij.org>" [full]

This means that the signature is valid and that you trust this key (either you signed it or someone you trusted did).

If you are not able to use an old version of GnuPG, you can still verify the file's SHA-1 checksum. This is less secure, because if someone modified the files as they were transferred to you, it would not be much more effort to modify the checksums that you see on this webpage. As such, if you use this method, you should compare the checksums with those in release announcement. This is sent to the gnupg-announce mailing list (among others), which is widely mirrored. Don't use the mailing list archive on this website, but find the announcement on several other websites and make sure the checksum is consistent. This makes it more difficult for an attacker to trick you into installing a modified version of the software.

Assuming you downloaded the file gnupg-2.2.41.tar.bz2, you can run the sha1sum command like this:

sha1sum gnupg-2.2.41.tar.bz2

and check that the output matches the SHA-1 checksum reported on this site. An example of a sha1sum output is:

8683ed39c5707313ff094f4758fbf779112ff0b7  gnupg-2.2.41.tar.bz2

For your convenience, all SHA-1 check-sums available for software that can be downloaded from our site, have been gathered below.

63dde155a8df0d5e1987efa5fc17438beca83ac1  gnupg-2.4.0.tar.bz2
5195ff17de15ffd8629bfd0f0b5dd2b2774295f2  gnupg-w32-2.4.0_20221216.exe
8683ed39c5707313ff094f4758fbf779112ff0b7  gnupg-2.2.41.tar.bz2
1de0b24d60e2628e491b1272f5a586aae3ca36f9  gnupg-w32-2.2.41_20221209.exe
82453e937568f783c210c25ba33cd738d95f08cc  gnupg-desktop-2.4.0.0.tar.xz
7850e24692d347384b423c0bdf7604372098e7e8  gnupg-desktop-2.4.0.0-x86_64.AppImage
a6e5efdd72e848aab4064e5ef4c6835ba344bcf1  libgpg-error-1.46.tar.bz2
de2cc32e7538efa376de7bf5d3eafa85626fb95f  libgcrypt-1.10.1.tar.bz2
e460dd48374a8a6d80aac341759f3b29507b10fa  libgcrypt-1.8.10.tar.bz2
7fe6d00b61e85a699a28d0aa309ba0bddcc46f3e  libksba-1.6.3.tar.bz2
ec4f67c0117ccd17007c748a392ded96dc1b1ae9  libassuan-2.5.5.tar.bz2
15028002a4c15d47d6037f45637e5ebc73b2ebd1  ntbtls-0.3.1.tar.bz2
f9d63e9747b027e4e404fe3c20c73c73719e1731  npth-1.6.tar.bz2
29daaf45f15cb5b8ec9b4a06284343f7a87082fb  pinentry-1.2.1.tar.bz2
d559f7994f9dfd1af611f1f14313b2abbea2a33b  gpgme-1.18.0.tar.bz2
3f8a0ba9c7821049d51b982141a2330a246beb55  scute-1.7.0.tar.bz2
61475989acd12de8b7daacd906200e8b4f519c5a  gpa-0.10.0.tar.bz2
13747486ed5ff707f796f34f50f4c3085c3a6875  gnupg-1.4.23.tar.bz2
d4c9962179d36a140be72c34f34e557b56c975b5  gnupg-w32cli-1.4.23.exe

For your convenience, all SHA-256 check-sums available for software that can be downloaded from our site, have been gathered below.

1d79158dd01d992431dd2e3facb89fdac97127f89784ea2cb610c600fb0c1483  gnupg-2.4.0.tar.bz2
0d4539afefaca0e0a0b0fe0d06baf207512a9520e38d680aaa90c1c57905cf48  gnupg-w32-2.4.0_20221216.exe
13f3291007a5e8546fcb7bc0c6610ce44aaa9b3995059d4f8145ba09fd5be3e1  gnupg-2.2.41.tar.bz2
72f24a6be29971951ca2cf5d42bb2fc4f25836389ce6afa8636ac1f402ad93bf  gnupg-w32-2.2.41_20221209.exe
cec8cfed0b21621c1e46cd333e573f47a1abcbf5a7f6debc4e010167a621da41  gnupg-desktop-2.4.0.0.tar.xz
5a5bf8c1a436e7239ba62cfa5cac42cb64a241b8e60d7e08cb9da50bf453754d  gnupg-desktop-2.4.0.0-x86_64.AppImage
b7e11a64246bbe5ef37748de43b245abd72cfcd53c9ae5e7fc5ca59f1c81268d  libgpg-error-1.46.tar.bz2
ef14ae546b0084cd84259f61a55e07a38c3b53afc0f546bffcef2f01baffe9de  libgcrypt-1.10.1.tar.bz2
6896915501f951e23d02dcb0453469c2cc22aa4d77a001ff73a2647c2d29e7dd  libgcrypt-1.8.10.tar.bz2
3f72c68db30971ebbf14367527719423f0a4d5f8103fc9f4a1c01a9fa440de5c  libksba-1.6.3.tar.bz2
8e8c2fcc982f9ca67dcbb1d95e2dc746b1739a4668bc20b3a3c5be632edb34e4  libassuan-2.5.5.tar.bz2
8922181fef523b77b71625e562e4d69532278eabbd18bc74579dbe14135729ba  ntbtls-0.3.1.tar.bz2
1393abd9adcf0762d34798dc34fdcf4d0d22a8410721e76f1e3afcd1daa4e2d1  npth-1.6.tar.bz2
457a185e5a85238fb945a955dc6352ab962dc8b48720b62fc9fa48c7540a4067  pinentry-1.2.1.tar.bz2
361d4eae47ce925dba0ea569af40e7b52c645c4ae2e65e5621bf1b6cdd8b0e9e  gpgme-1.18.0.tar.bz2
437fe758b27c243a5ee2535c6b065ea1d09f2c9a02d83567d2f934bb6395c249  scute-1.7.0.tar.bz2
95dbabe75fa5c8dc47e3acf2df7a51cee096051e5a842b4c9b6d61e40a6177b1  gpa-0.10.0.tar.bz2
c9462f17e651b6507848c08c430c791287cd75491f8b5a8b50c6ed46b12678ba  gnupg-1.4.23.tar.bz2