This is a DEVELOPER PREVIEW intended for developers and testers only.
DO NOT RUN THIS CODE ON A PRODUCTION SERVER. IT WILL INSTALL CERTIFICATES SIGNED BY A TEST CA, AND WILL CAUSE CERT WARNINGS FOR USERS.
Browser-trusted certificates will be available in the coming months.
For more information regarding the status of the project, please see https://letsencrypt.org. Be sure to checkout the Frequently Asked Questions (FAQ).
In short: getting and installing SSL/TLS certificates made easy (watch demo video).
The Let's Encrypt Client is a tool to automatically receive and install X.509 certificates to enable TLS on servers. The client will interoperate with the Let's Encrypt CA which will be issuing browser-trusted certificates for free.
It's all automated:
- The tool will prove domain control to the CA and submit a CSR (Certificate Signing Request).
- If domain control has been proven, a certificate will get issued and the tool will automatically install it.
All you need to do to sign a single domain is:
user@www:~$ sudo letsencrypt -d www.example.org certonly
For multiple domains (SAN) use:
user@www:~$ sudo letsencrypt -d www.example.org -d example.org certonly
and if you have a compatible web server (Apache or Nginx), Let's Encrypt can not only get a new certificate, but also deploy it and configure your server automatically!:
user@www:~$ sudo letsencrypt -d www.example.org run
Encrypt ALL the things!
- Supports multiple web servers:
- apache/2.x (tested and working on Ubuntu Linux)
- nginx/0.8.48+ (under development)
- standalone (runs its own simple webserver to prove you control a domain)
- The private key is generated locally on your system.
- Can talk to the Let's Encrypt (demo) CA or optionally to other ACME compliant services.
- Can get domain-validated (DV) certificates.
- Can revoke certificates.
- Adjustable RSA key bit-length (2048 (default), 4096, ...).
- Can optionally install a http -> https redirect, so your site effectively runs https only (Apache only)
- Fully automated.
- Configuration changes are logged and can be reverted.
- Text and ncurses UI.
- Free and Open Source Software, made with Python.
Official documentation, including installation instructions, is available at https://letsencrypt.readthedocs.org.
Documentation: https://letsencrypt.readthedocs.org
Software project: https://github.com/letsencrypt/letsencrypt
Notes for developers: https://letsencrypt.readthedocs.org/en/latest/contributing.html
Main Website: https://letsencrypt.org/
IRC Channel: #letsencrypt on Freenode
Community: https://community.letsencrypt.org
Mailing list: client-dev (to subscribe without a Google account, send an email to [email protected])