diff --git a/concepts/custom-types/about.md b/concepts/custom-types/about.md
index 55bb06a4..0dbeefa5 100644
--- a/concepts/custom-types/about.md
+++ b/concepts/custom-types/about.md
@@ -45,6 +45,6 @@ let describe flexibleNumber =
             "Invalid"
 ```
 
-[custom-types]: https://elmprogramming.com/type-system.html#creating-our-own-types
+[custom-types]: https://guide.elm-lang.org/types/custom_types.html
 [pattern-matching]: https://guide.elm-lang.org/types/pattern_matching.html
 [impossible-states]: https://www.youtube.com/watch?v=IcgmSRJHu_8
diff --git a/concepts/custom-types/introduction.md b/concepts/custom-types/introduction.md
index 054c07bb..60b45f37 100644
--- a/concepts/custom-types/introduction.md
+++ b/concepts/custom-types/introduction.md
@@ -45,6 +45,6 @@ let describe flexibleNumber =
             "Invalid"
 ```
 
-[custom-types]: https://elmprogramming.com/type-system.html#creating-our-own-types
+[custom-types]: https://guide.elm-lang.org/types/custom_types.html
 [pattern-matching]: https://guide.elm-lang.org/types/pattern_matching.html
 [impossible-states]: https://www.youtube.com/watch?v=IcgmSRJHu_8
diff --git a/concepts/custom-types/links.json b/concepts/custom-types/links.json
index acf45d6f..c4b649ac 100644
--- a/concepts/custom-types/links.json
+++ b/concepts/custom-types/links.json
@@ -1,6 +1,6 @@
 [
   {
-    "url": "https://elmprogramming.com/type-system.html#creating-our-own-types",
+    "url": "https://guide.elm-lang.org/types/custom_types.html",
     "description": "Custom Types"
   },
   {