testssl.sh is a free command line tool which checks a server's service on any port for the support of TLS/SSL ciphers, protocols as well as some cryptographic flaws.

• Clear output: you can tell easily whether anything is good or bad.
• Machine readable output (CSV, two JSON formats)
• No need to install or to configure something. No gems, CPAN, pip or the like.
• Works out of the box: Linux, OSX/Darwin, FreeBSD, NetBSD, MSYS2/Cygwin, WSL (bash on Windows). Only OpenBSD needs bash.
• A Dockerfile is provided, there's also an official container build @ dockerhub.
• Flexibility: You can test any SSL/TLS enabled and STARTTLS service, not only web servers at port 443.
• Toolbox: Several command line options help you to run your test and configure your output.
• Reliability: features are tested thoroughly.
• Privacy: It's only you who sees the result, not a third party.
• Freedom: It's 100% open source. You can look at the code, see what's going on.
• The development is open (GitHub) and participation is welcome.

This software is free. You can use it under the terms of GPLv2, see LICENSE.

Attribution is important for the future of this project -- also in the internet. Thus if you're offering a scanner based on testssl.sh as a public and/or paid service in the internet you are strongly encouraged to mention to your audience that you're using this program and where to get this program from. That helps us to get bugfixes, other feedback and more contributions.

Testssl.sh is working on every Linux/BSD distribution out of the box. Latest by 2.9dev most of the limitations of disabled features from the openssl client are gone due to bash-socket-based checks. As a result you can also use e.g. LibreSSL or OpenSSL >= 1.1.1 . testssl.sh also works on other unixoid systems out of the box, supposed they have /bin/bash >= version 3.2 and standard tools like sed and awk installed. An implicit (silent) check for binaries is done when you start testssl.sh . System V needs probably to have GNU grep installed. MacOS X and Windows (using MSYS2, Cygwin or WSL) work too.

Update notification here or @ mastodon or bluesky. Please note the twitter account is not being used anymore.

You can download testssl.sh branch 3.2 just by cloning this git repository:

git clone --depth 1 https://github.com/testssl/testssl.sh.git

3.2 is now the latest branch which evolved from 3.1dev. It's in the release candidate phase and considered as stable. For the former stable version named oldstable please help yourself by downloading the ZIP or tar.gz archive. Just cd to the directory created (=INSTALLDIR) and run it off there.

Testssl.sh has minimal requirements. As stated you don't have to install or build anything. You can just run it from the pulled/cloned directory. Still if you don't want to pull the GitHub repo to your directory of choice you can pull a container from dockerhub and run it:

docker run --rm -ti  drwetter/testssl.sh <your_cmd_line>

Or if you have cloned this repo you also can just cd to the INSTALLDIR and run

docker build . -t imagefoo && docker run --rm -t imagefoo example.com

For more please consult Dockerfile.md.

Usage of the program is without any warranty. Use it at your own risk.

Testssl.sh is intended to be used as a standalone CLI tool. While we tried to apply best practise security measures, we can't guarantee that the program is without any vulnerabilities. Running as a service may pose security risks and you're recommended to apply additional security measures.

We're currently in the release candidate phase for version 3.2. You should use it despite the label "RC". Bigger features will be developed in a separate branch before merged into a 3.3dev to avoid hiccups or inconsistencies.

Version 3.0.X receives bugfixes, labeled as 3.0.1, 3.0.2 and so on. This will happen until 3.2 is finally released.

Support for 2.9.5 has been dropped. Supported is >= 3.0.x only.

• .. it is there for reading. Please do so :-) -- at least before asking questions. See man page in groff, html and markdown format in ~/doc/.
• https://testssl.sh/ will help to get you started.
• For the (older) version 2.8, Will Hunt provides a longer description, including useful background information.

Contributions are welcome! See CONTRIBUTING.md for details. Please also have a look at the Coding Convention. A lot of contributors already helped to push the project where it currently is, see CREDITS.md. We still you use your help now. A start would be look for issues which are labeled as good first issue, for grabs or help wanted. The latter is more advanced.

In general there's some maintenance burden, like maintaining handshakes and CA stores, writing unit tests, improving github actions. If you believe you can contribute, speak up.

Bug reports are important. It makes this project more robust.

Please file bugs in the issue tracker @ GitHub. Do not forget to provide detailed information, see template for issue, and further details @ https://github.com/testssl/testssl.sh/wiki/Bug-reporting. Nobody can read your thoughts -- yet. And only agencies your screen ;-)

You can also debug yourself, see here.

Please address questions not specifically to the code of testssl.sh to the respective projects below.

• https://github.com/johannesschaefer/webnettools
• https://github.com/TKCERT/testssl.sh-webfrontend

• https://inspect.rapydblok.com (see also https://inspect.rapydblok.com/about)

• https://github.com/TKCERT/testssl.sh-masscan

• https://privacyscore.org

• https://github.com/dnmvisser/nagios-testssl (Python 3)
• https://gitgud.malvager.net/Wazakindjes/icinga2_plugins/src/master/check_testssl.sh (Shell)

• see #233 and https://github.com/Homebrew/homebrew

• https://github.com/bitsofinfo/testssl.sh-processor

• https://github.com/bitsofinfo/testssl.sh-alerts

• https://github.com/marketplace/actions/testssl-sh-scan