diff --git a/source/index.ts b/source/index.ts
index 3bf75ff..682f3d7 100644
--- a/source/index.ts
+++ b/source/index.ts
@@ -247,3 +247,7 @@ Object.defineProperties(is, {
 });
 
 export default is; // tslint:disable-line:no-default-export
+
+// For CommonJS default export support
+module.exports = is;
+module.exports.default = is;