diff --git a/package.json b/package.json
index aa7d6f7..147a1dd 100644
--- a/package.json
+++ b/package.json
@@ -40,7 +40,7 @@
   ],
   "license": "MIT",
   "dependencies": {
-    "bignumber.js": "~2.3.0"
+    "bignumber.js": "~4.0.0"
   },
   "devDependencies": {
     "babel": "~5.8.23",