How to Access Nested JSON Data in Python: A Step-by-Step Guide

This article explains how to correctly access nested data within a JSON file using Python. It identifies common errors and provides corrected code examples for accessing the value of 'site2' from a sample JSON file.

Question:

I have a JSON file 'file.json' as follows:

{
    'name':'runoob',
    'alexa':10000,
    'sites': {
        'site1':'www.runoob.com',
        'site2':'m.runoob.com',
        'site3':'c.runoob.com'
    }
}

Can I use the following 2 codes in Python to query the value of 'site2'?

Code 1:

import json

# load the JSON file
with open('file.json') as f:

# access the value of 'site2'
site2 = f.sites.site2

print(site2)

Code 2:

import json

# load the JSON file
with open('file.json') as f:

# access the value of 'site2'
site2 = f['sites']['site2']

print(site2)

Answer:

No, both codes will not work as they have some syntax errors.

Code 1 Error:

After opening the JSON file, you need to parse the JSON data using the json.load() function to convert it into a Python object. Also, to access the value of 'site2', you need to use the dictionary syntax for nested objects. So the correct code would be:

import json

# load the JSON file
with open('file.json') as f:
    data = json.load(f)

# access the value of 'site2'
site2 = data['sites']['site2']

print(site2)

Code 2 Error:

You are trying to access the 'sites' property of the file object f, which is not possible as it is just a file handle. So you need to parse the JSON data first using json.load(). The correct code would be:

import json

# load the JSON file
with open('file.json') as f:
    data = json.load(f)

# access the value of 'site2'
site2 = data['sites']['site2']

print(site2)

By using json.load(), you convert the JSON data into a Python dictionary, enabling you to access its elements using the dictionary syntax.