diff --git a/types/align-text/index.d.ts b/types/align-text/index.d.ts
index 652eb5f453..0ceaa5e545 100644
--- a/types/align-text/index.d.ts
+++ b/types/align-text/index.d.ts
@@ -31,7 +31,7 @@ interface Callback {
         | TransformResult;
 }
 
-declare function align_text(text: string, fn: number | Callback): string;
-declare function align_text(text: string[], fn: number | Callback): string[];
+declare function align_text(text: string, fn?: number | Callback): string;
+declare function align_text(text: string[], fn?: number | Callback): string[];
 
 export = align_text;
diff --git a/types/align-text/test/simple.ts b/types/align-text/test/simple.ts
index 0571e5aad0..65ef81fcf0 100644
--- a/types/align-text/test/simple.ts
+++ b/types/align-text/test/simple.ts
@@ -4,3 +4,5 @@ const text = ["abc", "abc", "abc"];
 align(text, 4);
 
 align("abc", 2);
+
+align("abc");