How to PrettyPrint a JSON File with Python?

Introduction

JSON (JavaScript Object Notation) is a data format used in many applications and programming languages. The file format is compact and commonly appears in client-server applications, such as API responses.

When viewing JSON files in Python, PrettyPrint helps format the text in a visually pleasing format.

This guide shows different ways to PrettyPrint the JSON file format using Python.

Prerequisites

• Python 3 installed and configured.
• An IDE or text editor to write the code.
• A way to run the code, such as the terminal.

How to PrettyPrint JSON in Python?

Depending on the input and output format, there are various ways to PrettyPrint a JSON file using Python. Below is a list of different methods with steps.

Method 1: Using json

The json library contains all the necessary functions to work with JSON data. The json.dumps method automatically PrettyPrints parsed JSON data.

To see how it works, do the following:

1. Create a file named my_file.json with the following contents:

{"employees":[{"name":"bob","sector":"devops"},{"name":"alice","sector":"infosec"}]}

2. The code below demonstrates how to import and PrettyPrint a JSON file in Python:

import json

my_file = open("my_file.json")
loaded_json = json.load(my_file)

print(json.dumps(loaded_json, indent=2))

The code does the following:

• Opens the file called my_file.json and saves it to the variable my_file. (Check out our guide on how to handle files in Python for more details.)
• Loads the JSON into loaded_json using the json.loads method.
• PrettyPrints the loaded JSON file using the json.dumps method. The indentation level is two spaces.

The output looks like this:

{
  "employees": [
    {
      "name": "bob",
      "sector": "devops"
    },
    {
      "name": "alice",
      "sector": "infosec"
    }
  ]
}

PrettyPrinting adds proper indentation for every nested object and spaces after commas (,) and colons (:).

Method 2: Using pprint

Use the pprint library to pretty print JSON files as strings. For example:

import json
import pprint

my_file = open("my_file.json")
loaded_json = json.load(my_file)

pprint.pprint(loaded_json)

The pprint method replaces double quotes with single quotes, which means the result is not in JSON format explicitly.

Method 3: Using the Terminal

Use the json.tool to PrettyPrint JSON files directly in the terminal. Use the following command format:

python3 -m json.tool my_file.json

The JSON file contents print to the output with indentation level four.

Conclusion

After going through the methods in this guide, you know how to PrettyPrint a JSON file using Python in various ways.

Next, learn how to add items to a dictionary in Python.