How to pretty print log output in Chrome DevTools Console?

You could format the data as JSON:

console.log(JSON.stringify({foo:1, bar:2}, null, 4));

{
    "foo": 1,
    "bar": 2
} 

If you are at a breakpoint, you can call JSON.stringify() directly from the Chrome DevTools console:

>  JSON.stringify(anObject, null, 2);
<- "{
     "field": "foo",
     "array": [
       {
         "element": 1
       },
       {
         "element": 2
       }
     ],
     "object": {
       "inner_field": "bar"
     }
   }"
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