How to concatenate 2 fields in JSON using JQ

Suppose you have the following JSON input:

  "firstName": "Charles",
  "lastName": "Doe",
  "age": 41,
  "location": {
    "city": "San Fracisco",
    "postalCode": "94103"
  "hobbies": [

If you want to concatenate the firstName and lastName fields, you can do the following filter

{fullName: (.firstName + " " + .lastName)}

This will produce the following output:

  "fullName": "Charles Doe"

You can try that example in our JQ playground here

See other online JQ resources

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