diff --git a/package.json b/package.json
index 38bdf8e..c486b6c 100644
--- a/package.json
+++ b/package.json
@@ -42,7 +42,7 @@
     "babel-eslint": "^7.2.1",
     "babel-preset-env": "^1.3.2",
     "babel-preset-stage-0": "^6.22.0",
-    "chai": "^3.5.0",
+    "chai": "^4.0.2",
     "coveralls": "^2.13.0",
     "eslint-config-airbnb-deps": "^15.0.1",
     "eslint-plugin-babel": "^4.1.1",