diff --git a/package.json b/package.json
index f6ba545..e82285a 100644
--- a/package.json
+++ b/package.json
@@ -24,7 +24,7 @@
     "prepush": "npm test"
   },
   "devDependencies": {
-    "chai": "3.5.0",
+    "chai": "4.1.2",
     "coveralls": "2.13.3",
     "dependency-check": "2.10.1",
     "eslint": "3.19.0",