Handling JSON Errors

External JSON data may be malformed. Trying to parse invalid JSON raises JSONDecodeError.

import json

bad_json = '{"name": "Alice", age: 30}'  # Missing quotes around age

try:
    data = json.loads(bad_json)
except json.JSONDecodeError as e:
    print(f"Invalid JSON: {e}")

The error tells you where parsing failed:

Expecting property name enclosed in double quotes: line 1 column 19

Always wrap loads() in try/except when dealing with external data - API responses, user input, files from unknown sources.

Common JSON syntax errors:

• Single quotes instead of double quotes
• Trailing commas after the last item
• Unquoted property names
• Comments (JSON doesn't support them)

I cover error handling patterns in my JSON with Python course.