diff --git a/src/index.d.ts b/src/index.d.ts
index 961232e..6859402 100644
--- a/src/index.d.ts
+++ b/src/index.d.ts
@@ -1,6 +1,6 @@
 export const FS: {
     writeFile: (fileName: string, binaryData: Uint8Array) => void,
-    readFile: (fileName: string) => void,
+    readFile: (fileName: string) => Uint8Array,
     unlink: (fileName: string) => void,
 }