Python Read JSON File: Methods and Examples

How to Read a JSON File Using json.load()

The most common way to read a JSON file in Python is with json.load().

First, import the built-in json module:

import json

Then open the file and load its contents:

import json

with open(“data.json”, “r”) as file:

data = json.load(file)

print(data)

The with open() statement automatically closes the file after Python finishes reading it.

The “r” mode means the file is opened for reading.

How to Access Data from a JSON File?

After reading a JSON object, Python usually stores it as a dictionary.

Suppose data.json contains:

{

"name": "Alex",

"role": "Developer",

"location": "Remote"

}

You can access individual values using dictionary keys:

import json

with open("data.json", "r") as file:

data = json.load(file)

print(data["name"])

print(data["role"])

print(data["location"])

Output:

Alex

Developer

Remote

This approach is useful when you know the names of the fields you want to retrieve.

How to Read Nested JSON Data in Python?

JSON files can contain nested objects.

For example:

{

"employee": {

"name": "Alex",

"department": {

"name": "Engineering",

"location": "Remote"

}

}

}

After loading the file, you can access nested values using multiple dictionary keys:

import json

with open("data.json", "r") as file:

data = json.load(file)

department = data["employee"]["department"]["name"]

print(department)

Output:

Engineering

Understanding the structure of the JSON document is important when accessing nested data.

How to Read a JSON Array in Python?

A JSON file can also contain an array of objects.

For example:

[

{

"name": "Alex",

"role": "Developer"

},

{

"name": "Jordan",

"role": "Designer"

}

]

Python reads this as a list:

import json

with open("employees.json", "r") as file:

employees = json.load(file)

for employee in employees:

print(employee["name"], employee["role"])

Output:

Alex Developer

Jordan Designer

This is a common structure for JSON datasets and API responses.

How to Read a JSON File with UTF-8 Encoding?

If the JSON file contains non-ASCII characters, explicitly specifying UTF-8 encoding can be helpful.

import json

with open("data.json", "r", encoding="utf-8") as file:

data = json.load(file)

print(data)

Using an explicit encoding makes the expected character encoding clear and can help avoid encoding-related issues when processing files across different environments.

How to Handle JSON File Errors in Python?

A JSON file may be missing, inaccessible, or contain invalid JSON syntax. Using exception handling makes your application more reliable.

import json

try:

with open("data.json", "r", encoding="utf-8") as file:

data = json.load(file)

print(data)

except FileNotFoundError:

print("The JSON file was not found.")


except json.JSONDecodeError:

print("The file contains invalid JSON.")

except OSError as error:

print(f"Unable to read the file: {error}")

Here:

• FileNotFoundError handles a missing file.
• JSONDecodeError handles malformed JSON.
• OSError handles other file-related problems.

FileNotFoundError

This usually occurs when Python cannot find the specified file.

with open(“missing.json”, “r”) as file:

data = json.load(file)

Check the filename and path, or use an absolute path when appropriate.

JSONDecodeError

This occurs when the file contents aren’t valid JSON.

For example, JSON requires double quotes around object keys and string values:

{

"name": "Alex"

}

Using invalid JSON syntax such as this can cause parsing errors:

{'name': 'Alex'}

The second example resembles a Python dictionary but isn’t valid standard JSON because it uses single quotes.

KeyError

A KeyError can occur when trying to access a key that doesn’t exist:

name = data["username"]

If the JSON uses “name” instead, you can use:

name = data.get("name")

or check whether the key exists first.