JSON Validator & Formatter: How to Fix Invalid JSON Fast (Without Installing Anything)

Pretty printing JSON in Python is achieved using json.dumps with the indent parameter. However, users often encounter TypeError with datetime objects, encoding issues, and JSONDecodeError. Additionally, common JSON validation errors include trailing commas, the use of single quotes instead of double quotes, unquoted keys, and the inclusion of comments. These mistakes render JSON invalid, as the format strictly requires double quotes for keys and values and prohibits comments or trailing commas in files.