diff --git a/package.json b/package.json
index 45036d4..71068b8 100644
--- a/package.json
+++ b/package.json
@@ -34,7 +34,7 @@
     "build": "npm run build:js && npm run build:types",
     "build:js": "rollup -c",
     "build:types": "tsc -p tsconfig.typedef.json",
-    "postbuild:types": "echo \"// Minimum TypeScript Version: 4.1\n\n$(cat types/index.d.ts)\" > types/index.d.ts",
+    "postbuild:types": "echo \"// Minimum TypeScript Version: 4.2\n\n$(cat types/index.d.ts)\" > types/index.d.ts",
     "presize": "npm run build:js",
     "size": "terser --compress --mangle -- ./dist/umd.js | gzip -c | wc -c",
     "pretest": "npm run build:js",