Babel standalone use in the browser

index.html

<div id="root"></div>
<script src="https://cdnjs.cloudflare.com/ajax/libs/babel-standalone/6.21.1/babel.min.js"></script>
<script>
  Babel.registerPreset("custom-preset", {
    presets: [
      [Babel.availablePresets["es2015"]],
    ],
    plugins: [
      Babel.availablePlugins["syntax-jsx"],
      [Babel.availablePlugins["transform-react-jsx"], {
        "pragma": "jsx.dom",
        "pragmaFrag": "jsx.Fragment",
      }]
    ],
  });
</script>

<script type="text/babel" data-presets="custom-preset">
  const foo = () => (<p>Foo Bar</p>);

  console.log(foo)
</script>