Text & Developer 2 min read
How to Format, Validate and Minify JSON (and Convert JSON to CSV)
Fix messy JSON, spot syntax errors, minify it for production and convert between JSON and CSV — with common mistakes explained.
JSON is the standard way APIs and apps exchange data, but a single missing comma makes the whole thing fail. A formatter makes JSON readable and a validator tells you exactly where it broke.
Format (beautify) JSON
Paste your JSON into the JSON Formatter. It adds indentation and line breaks so nested objects are easy to read, and flags errors if the JSON is invalid.
JSON Formatter
Format and validate JSON free — in your browser.
The most common JSON errors
- Trailing comma after the last item in an object or array
- Single quotes instead of double quotes around keys and strings
- Unquoted keys — keys must be in double quotes
- Comments — standard JSON does not allow them
- Missing brackets or braces
Minify JSON for production
Whitespace is useful for humans but wasted bytes for machines. The JSON Minifier removes it, shrinking payloads and speeding up API responses.
Convert between JSON and CSV
- JSON to CSV turns an array of objects into rows for Excel or Google Sheets.
- CSV to JSON turns spreadsheet data into JSON for apps and APIs.
Frequently asked questions
How do I check if my JSON is valid?
Paste it into the JSON Formatter. If it is invalid, you get an error message pointing at the problem.
What is the difference between formatting and minifying?
Formatting adds whitespace for readability; minifying removes it to make the file smaller.
Can I convert nested JSON to CSV?
CSV is flat, so nested data is usually flattened or best handled by converting an array of simple objects.
