pretty simple one..

example

github

Just add the following URL to External Resources in jsfiddle, you will see console.log and console.error in the result screen.

• click on that arrow next to JavaScript
• and as FRAMEWORKS & EXTENSIONS select No-Libary (Pure JS)
• paste your console.log('foo'); in JS box
• under Resources add
  • or: under Resources add
• and run your script hitting that Play button

I couldn't find any option for selecting the Firebug extension in the JavaScript gear option, and I didn't want to add external links/libraries, but there is another simple solution.

You can use your browser's built in console

works fine... here

var consoleLine = "<p class=\"console-line\"></p>";

console = {
    log: function (text) {
        $("#console-log").append($(consoleLine).html(text));
    }
};
console.log("Hello Console")

None of the above solutions worked for me, since I needed an interactive console to be able to dynamically set a variable when testing reactivity in Vue.js.

So I switched to Codepen, which has a an interactive console scoped to your application.

There are several ways to embed a virtual console inside of any web page...

1. Firebug Lite Debugger ^Demo

Include the following script from Firebug Lite, served via raw.githack.com:

2. Stack Snippets Virtual Console ^Demo

Include the following script from /u/canon, used in Stack Snippets:

3. Add jsFiddle Console ^Demo

Include the following script from eu81273, served via raw.githack.com :

4. Roll You Own

Here's a trivial implementation that wraps the existing console.log call and then dumps out the prettified arguments using document.write:

var oldLog = window.console.log
window.console.log = function(...args) {
    document.write(JSON.stringify(args, null, 2));
    oldLog.apply(this, args);
}

console.log("String", 44, {name: "Kyle", age: 30}, [1,2,3])

Further Reading

• Print Var in JsFiddle

For future reference: the jsfiddle-console from answer was exactly what I needed when teaching a class on JavaScript. However I found it to be too limited to be of any actual use in this situation. So I made my own.

Maybe it will serve anyone here.

Just add the CDN-version to the resources of jsFiddle:

Example here:

GitHub:

I might be late to the party but just wanted to mention that JSfiddle has just released the new console feature. Just turn it on in the Settings if it doesn't work for you.

Still in beta but hey... no more annoying workarounds.