JSON Formatter
Format, minify, and validate JSON
Format, Minify, and Validate JSON
This free JSON formatter turns compact or hard-to-read JSON into an indented structure, minifies valid JSON to a single line, and checks whether the input follows JSON syntax. It is useful for API responses, configuration files, logs, debugging, and preparing payloads for development tools.
Paste JSON into the input field and choose Format, Minify, or Validate. Processing happens locally in your browser, so the data you paste is not uploaded by this tool. Avoid sharing secrets in any online workflow, and remove API keys or personal data before copying results elsewhere.
Frequently Asked Questions
Why is my JSON invalid?
Common causes include trailing commas, single quotes, unquoted property names, comments, or missing brackets. Standard JSON requires double-quoted keys and string values.
What is the difference between formatting and minifying?
Formatting adds indentation and line breaks for readability. Minifying removes unnecessary whitespace to make the same data more compact.
Does formatting change the data?
No. The tool validates the JSON, then changes only whitespace outside strings. Original number tokens, including integers larger than JavaScript's safe range, remain unchanged.