About the JSON Formatter
Tezmy's JSON Formatter turns messy or minified JSON into clean, readable, properly indented JSON. It validates as it formats and points to the exact line and column of any mistake, like a missing comma or an extra bracket. You can also minify JSON to make it as small as possible and sort keys alphabetically to compare files more easily. Because everything runs in your browser, it is safe to use with private API responses and config files.
Updated October 2026
How to use the JSON Formatter
- 1Paste your JSON into the left box, or press “Try a sample”.
- 2Press Format to beautify it, or Minify to shrink it.
- 3If something is wrong, read the error with its line and column, fix it and try again.
- 4Copy the result or download it as a .json file.
The most common JSON errors
The formatter shows the exact line and column of the first error, so you can jump straight to it.
- A missing comma between two items, or an extra comma after the last one.
- Keys or text in single quotes: JSON needs double quotes.
- Comments: standard JSON doesn't allow // or /* */ comments.
- Missing closing brackets or braces in long files.
Beautify, minify and sort
Beautify adds indentation (2 spaces, 4 spaces or tabs) so nested data is easy to read. Minify removes every unneeded space to make the file as small as possible for APIs and configs. Sorting keys alphabetically makes two versions of the same data easy to compare, especially together with the Diff Checker.
Who uses a JSON formatter?
- Developers reading API responses and debugging requests.
- Anyone editing config files for apps, games or websites.
- Data analysts checking exported data.
- Students learning how JSON is structured.
Safe for private data
API responses and config files often contain tokens, emails or customer data. Here the formatting happens in your own browser, so nothing is uploaded or logged. You can download the formatted result as a .json file. If the data came from a spreadsheet, the CSV to JSON Converter produces the text first, and the Word Counter shows how long the result is.
Features
- Beautify with 2 spaces, 4 spaces or tabs
- Validation with exact line and column of errors
- Minify to the smallest size
- Sort keys alphabetically
- Download as a .json file
- Private: your data never leaves your browser
Frequently asked questions
What is a JSON formatter?
A JSON formatter, also called a JSON beautifier or pretty printer, adds line breaks and indentation to JSON so it is easy for people to read. It does not change the data itself.
How do I know if my JSON is valid?
Paste it in and press Format. Valid JSON is formatted and marked valid. Invalid JSON shows an error message with the line and column where the problem is.
What are the most common JSON errors?
Missing or extra commas, single quotes instead of double quotes, keys without quotes, trailing commas after the last item, and comments. Standard JSON does not allow any of these.
What does minify do?
Minify removes all spaces and line breaks that are not needed. The data stays exactly the same but the file becomes smaller, which is useful for sending over a network.
Is it safe to paste sensitive data?
Yes. Formatting happens entirely in your browser. Your JSON is never uploaded, logged or stored.
How do I format JSON on my phone?
Paste the JSON into the box in any mobile browser and tap Format; copy the result back with one tap.
Can it convert JSON to CSV?
Use our CSV to JSON converter, which also works in the other direction.
Does it fix my JSON automatically?
It points to the exact error so you can fix it yourself, because guessing what you meant could change your data.
Is it free?
Yes. No sign-up and no size limit beyond what your browser can handle.