Code HTML Online

About this Project is a free tool companion of the Mastery HTML5 course at Udemy, where you can code and test HTML, CSS and JavaScript and run it quickly in your desktop and in your mobile device without setting up a server.

It started as a project for my trainings at different companies and workshops at conferences over the world. It uses the powerful open source ACE as the code editor and a custom solution for connecting to a mobile browser.

If you need to contact me, you can do it by Twitter @firt or check my website for other contact details.

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With this tool you can write Websites and Progressive Web Apps with HTML, CSS and JavaScript and run them in your mobile device (phone or tablet) for learning purposes.

You can write one external JavaScript file, one CSS file and one Manifest besides the HTML and you are allowed to load other files from CDNs or other servers.

There are several resources available that you can point to inside the HTML as relative files, such as:

  • Low resolution image: photo.jpg
  • High resolution image: photo_hi.jpg
  • 360 Panorama: pano.jpg
  • Animated GIF: animation.gif
  • Video: video.mp4
  • SVG: logo.svg
  • Transparent Icon: icon.png
  • iOS Icon: icon_ios.png
  • Basic Service Worker: sw.js

Connect to a Mobile Device

Please wait... We are creating your personal access for your mobile device.

Scan the QR code on phone/tablet

You can also type in your mobile browser. Once you have loaded the website in your device, you can continue working on the project and then use Save and reload the browser on your mobile device without connecting again.