Pen Settings
HTML
CSS
JavaScript
About JavaScript Preprocessors
JavaScript preprocessors can help make authoring JavaScript easier and more convenient. For instance, CoffeeScript can help prevent easy-to-make mistakes and offer a cleaner syntax and Babel can bring ECMAScript 6 features to browsers that only support ECMAScript 5.
Add External Scripts/Pens
Any URL's added here will be added as <script>s in order, and run before the JavaScript in the editor. You can use the URL of any other Pen and it will include the JavaScript from that Pen.
About External Resources
You can apply a script from anywhere on the web to your Pen. Just put a URL to it here and we'll add it, in the order you have them, before the JavaScript in the Pen itself.
If the script you link to has the file extension of a preprocessor, we'll attempt to process it before applying.
You can also link to another Pen here, and we'll pull the JavaScript from that Pen and include it. If it's using a matching preprocessor, we'll combine the code before preprocessing, so you can use the linked Pen as a true dependency.
Behavior
Save Automatically?
If active, Pens will autosave every 30 seconds after being saved once.
Auto-Updating Preview
If enabled, the preview panel updates automatically as you code. If disabled, use the "Run" button to update.
Format on Save
If enabled, your code will be formatted when you actively save your Pen. Note: your code becomes un-folded during formatting.
Editor Settings
Want to change your Syntax Highlighting theme, Fonts and more?
Visit your global Editor Settings.