diff --git a/index.d.ts b/index.d.ts
index 74b2acd2cc..ae364e5c1e 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1,3 +1,5 @@
+/// <reference lib="DOM" />
+
 export interface AxiosTransformer {
   (data: any, headers?: any): any;
 }
diff --git a/package.json b/package.json
index 3cde50dfbe..ecd3d7ef45 100644
--- a/package.json
+++ b/package.json
@@ -63,7 +63,7 @@
     "minimist": "^1.2.0",
     "mocha": "^5.2.0",
     "sinon": "^4.5.0",
-    "typescript": "^2.8.1",
+    "typescript": "^3.9.7",
     "url-search-params": "^0.10.0",
     "webpack": "^1.13.1",
     "webpack-dev-server": "^1.14.1"