diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index 3bf69f1..621aabe 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -110,6 +110,7 @@ In `dev` mode, Cannery will listen for these environment variables at runtime.
 - `POOL_SIZE`: Controls the pool size to use with PostgreSQL. Defaults to `10`.
 - `REGISTRATION`: Controls if user sign-up should be invite only or set to public. Set to `public` to enable public registration. Defaults to `invite`.
 - `LOCALE`: Sets a custom locale. Defaults to `en_US`.
+  - Available options: `en_US`, `de`, and `fr`
 
 ## `MIX_ENV=test`
 
diff --git a/README.md b/README.md
index bca5ad1..76d597d 100644
--- a/README.md
+++ b/README.md
@@ -63,7 +63,8 @@ You can use the following environment variables to configure Cannery in
   with `docker run -it shibaobun/cannery mix phx.gen.secret` and set for server to start.
 - `REGISTRATION`: Controls if user sign-up should be invite only or set to
   public. Set to `public` to enable public registration. Defaults to `invite`.
-- `LOCALE`: Sets a custom locale. Defaults to `en_US`.
+- `LOCALE`: Sets a custom locale. Defaults to `en_US`
+  - Available options: `en_US`, `de`, and `fr`
 - `SMTP_HOST`: The url for your SMTP email provider. Must be set
 - `SMTP_PORT`: The port for your SMTP relay. Defaults to `587`.
 - `SMTP_USERNAME`: The username for your SMTP relay. Must be set!