diff --git a/docs/content/reference/file-upload.md b/docs/content/reference/file-upload.md
index 3d4d4ea1067..8cc23d7a937 100644
--- a/docs/content/reference/file-upload.md
+++ b/docs/content/reference/file-upload.md
@@ -40,7 +40,7 @@ type Query {
 
 "The `Mutation` type, represents all updates we can make to our data."
 type Mutation {
-    singleUpload(file: Upload!): Bool!
+    singleUpload(file: Upload!): Boolean!
 }
 ```