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Latest commit 0b1b3a2 Feb 21, 2018
april Merge pull request #335 from april/extended-validation
Add support for an extended validation certificate

Visit for a list of test subdomains, including:

Server Setup

Stock Ubuntu VM, DNS A records for and * pointing to the VM.

Testing and development

  1. Follow the instructions to install Docker.

  2. Clone into the badssl repo by running git clone && cd

  3. In order to access the various badssl subdomains locally you will need to add them to your system hosts file. Run make list-hosts and copy and paste the output into /etc/hosts.

  4. Start Docker by running make serve.

  5. You can now navigate to badssl.test in your browser, and you should see a certificate error.

  6. The badssl root certificate is at certs/sets/test/gen/crt/ca-root.crt. In order to get the rest of the badssl subdomains working, you will need to add this to your machine's list of trusted certificates.

    • On macOS, drag certs/sets/test/gen/crt/ca-root.crt into the login section of the program Keychain Access. A BadSSL Root Certificate Authority entry should appear in the list. Double-click on this entry and select "Always Trust" from the drop-down menu next to "Secure Sockets Layer (SSL)." Close the window to save your changes.

      If you are already familiar with this process, you can instead run this command:

      security add-trusted-cert -r trustRoot -p ssl \
        -k "$HOME/Library/Keychains/login.keychain" certs/sets/test/gen/crt/ca-root.crt
  7. In order to preserve the client and root certificates even after running make clean, run:

cd certs/sets/test
mkdir -p pregen/crt pregen/key
cp gen/crt/ca-root.crt pregen/crt/ca-root.crt
cp gen/crt/client.crt pregen/crt/client.crt
cp gen/crt/client-ca-root.crt pregen/crt/client-ca-root.crt
cp gen/key/ca-root.key pregen/key/ca-root.key
cp gen/key/client.key pregen/key/client.key
cp gen/key/client-ca-root.key pregen/key/client-ca-root.key

Acknowledgments is hosted on Google Cloud infrastructure and co-maintained by:

Several public certificates required special issuance processes. Most certificates were graciously issued for free, thanks to help from:

Various subdomains and test pages are also implemented by external contributors.

Disclaimer is meant for manual testing of security UI in web clients.

Most subdomains are likely to have stable functionality, but anything could change without notice. If you would like a documented guarantee for a particular use case, please file an issue. (Alternatively, you could make a fork and host your own copy.) is not an official Google product. It is offered "AS-IS" and without any warranties.