Certificate Compatibility

Last updated: December 05, 2016 | See all Documentation

Let’s Encrypt aims to be compatible with as much software as possible without compromising security. The main determining factor for whether a platform can validate Let’s Encrypt certificates is whether that platform includes IdenTrust’s DST Root X3 certificate in its trust store. A secondary factor is whether the platform supports modern SHA-2 certificates, since all Let’s Encrypt certificates use SHA-2.

If your certificate validates on some of the “Known Compatible” platforms but not others, the problem may be a web server misconfiguration, most likely failure to provide the correct certificate chain. Test your site with SSL Labs’ Server Test. If that doesn’t identify the problem, ask for help in our Community Forums.

You may want to visit this particular community forum discussion for more information about compatibility.

Known Compatible

Possibly Incompatible

Known Incompatible