diff --git a/README.md b/README.md
index 515f038..3b5cd00 100755
--- a/README.md
+++ b/README.md
@@ -3,5 +3,6 @@
 Automatically generates Let's Encrypt certificates using a lightweight Docker container without requiring any ports to be exposed for DNS challenges.
 
 Variables:
-#TODO: Add list of variables once main implementation is complete
-
+* `DUCKDNS_TOKEN`: Duck DNS Account Token
+* `DUCKDNS_DOMAIN`: Full Duck DNS domain (e.g. `test.duckdns.org`)
+* `LETSENCRYPT_EMAIL`: Email used for certificate renewal notifications