diff --git a/README.md b/README.md
index cd5bde0..000dd35 100644
--- a/README.md
+++ b/README.md
@@ -351,6 +351,7 @@ Only main chapters:
:small_orange_diamond: Useless CSP - public list about CSP in some big players (might make them care a bit more).
:small_orange_diamond: Why No HTTPS? - list of the world's top 100 websites by Alexa rank not automatically redirecting insecure requests.
:small_orange_diamond: cipherli.st - strong ciphers for Apache, Nginx, Lighttpd and more.
+ :small_orange_diamond: dhtool - public Diffie-Hellman parameter service/tool.
:small_orange_diamond: badssl.com - memorable site for testing clients against bad SSL configs.
:small_orange_diamond: tlsfun.de - registered for various tests regarding the TLS/SSL protocol.
:small_orange_diamond: CAA Record Helper - generate a CAA policy.