diff --git a/lib/string.ts b/lib/string.ts
index 0b24a256..a951adbd 100644
--- a/lib/string.ts
+++ b/lib/string.ts
@@ -1,3 +1,3 @@
-export function stripTags(s) {
+export function stripTags(s: string): string {
   return s.replace(RegExp('</?[^<>]*>', 'gi'), '')
 }