diff --git a/types/rangy/index.d.ts b/types/rangy/index.d.ts
index b6615b9aad..4a3afc08a1 100644
--- a/types/rangy/index.d.ts
+++ b/types/rangy/index.d.ts
@@ -31,6 +31,7 @@ interface RangyRange extends Range {
     equals(range:RangyRange):boolean;
     refresh():any;
     select():any;
+    toCharacterRange(containerNode:Node):{start:number, end:number};
 }
 
 interface RangySelection extends Selection {