diff --git a/README.md b/README.md
index 6d289a9..b23ae88 100644
--- a/README.md
+++ b/README.md
@@ -169,6 +169,12 @@ import 'mdn-polyfills/MouseEvent'; // 281 bytes
 import 'mdn-polyfills/CustomEvent'; // 279 bytes
 ```
 
+### [Number.isNaN](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Number/isNaN#Polyfill)
+
+```js
+import 'mdn-polyfills/Number.isNaN'; // 53 bytes
+```
+
 # License
 
 The mdn-polyfills as a module is licensed under MIT © [Michał Jezierski](https://github.com/msn0)<br/>
diff --git a/package.json b/package.json
index bf8f81e..bcecffb 100644
--- a/package.json
+++ b/package.json
@@ -29,6 +29,7 @@
     "closest",
     "toggleAttribute",
     "matches",
+    "isNaN",
     "Object.assign",
     "Object.create",
     "Array.of",
@@ -54,6 +55,7 @@
     "Element.prototype.matches",
     "MouseEvent",
     "CustomEvent",
+    "Number.isNaN",
     "polyfills",
     "polyfill",
     "mdn"
diff --git a/rollup.build.js b/rollup.build.js
index 875c5f7..2ecc3ae 100644
--- a/rollup.build.js
+++ b/rollup.build.js
@@ -48,3 +48,4 @@ rollup(input('./src/Element.prototype.toggleAttribute/index.js')).then(output('.
 rollup(input('./src/Element.prototype.matches/index.js')).then(output('./Element.prototype.matches.js'));
 rollup(input('./src/MouseEvent/index.js')).then(output('./MouseEvent.js'));
 rollup(input('./src/CustomEvent/index.js')).then(output('./CustomEvent.js'));
+rollup(input('./src/Number.isNaN/index.js')).then(output('./Number.isNaN.js'));