---

title: "JavaScript Import Map" date: "2025-04-13" tags: []

An import map is JSON that browsers use to resolve the path of JS modules when used in import and import() statements.

An example can be found on three.js:

<script type="importmap">
  {
    "imports": {
      "three": "https://unpkg.com/three@0.149.0/build/three.module.js"
    }
  }
</script>

<script type="module">
  import * as THREE from 'three';
  const scene = new THREE.Scene();
</script>

Another example commonly seen in micro-frontends:

<script type="importmap">
  {
    "imports": {
      "react": "https://unpkg.com/react@18.2.0/umd/react.production.min.js",
      "react-dom": "https://unpkg.com/react-dom@18.2.0/umd/react-dom.production.min.js"
    }
  }
</script>

<script type="module">
  import * as React from 'react';
  import * as ReactDOM from 'react-dom';
</script>