ZeroSSL: FREE SSL

Free SSL Certificates and Free SSL Tools for your website.

FREE SSL Certificate Wizard

Free certificates trusted by all major browsers issued in a few mouse clicks.

Self-Signed Certificate Generator

One-click generator of self-signed certificates for testing or internal purposes.

CSR Generator

Super-easy way to create Certificate Signing Requests.

Installable package

You can run a software package which obtains SSL certificates on your own server if you like. The software consists of a library and a client developed at Domain Knowledge Ltd. You can use the provided client application to easily issue and renew SSL certificates for your sites automatically, you can extend its functionality, or you can even build your own client application using the provided library (with some knowledge of Perl programming language).

If you do not want to install anything and just want your Free SSL Certificate, then you can use our online tools and have one issued for you in minutes right away. The process does not require deep technical knowledge and all you need to know is for which domain the certificate should be issued. Please note that NO private information (including RSA Keys, CSR and Certificate) is ever transmitted to the server. All communication between your browser and the server is also encrypted. The resulting certificate is trusted by all major browsers.

Our software supports:

Automatic registration

Your account key will be generated automatically and registered with Let's Encrypt.

Automatic CSR generation

Your domain key and Certificate Signing Request will be generated automatically for you if you don't have them yet.

Domain verification handling

The files required to prove your ownership of the domain will be automatically created for you.

Conditional renew

You can set how many days before expiration should be left for the renewal process to run.

Integration with external modules

Our software can be easily extended with external modules, handling all important steps of the process.

Certificate revocation

You can revoke your certificate at any moment.

Get in touch

If you want to provide feedback or if you want a customized solution developed just for you, get in touch with us.
If you are hiring and based in London, UK or around Vienna, Austria - maybe we could work for you!