JSON Formatter & Validator
Paste JSON below to format, minify, or validate it. All processing is done in your browser.
About JSON Formatting
Also called "pretty-printing", it adds indentation and newlines so JSON data is easy for humans to read. The data itself remains identical.
Removes all unnecessary whitespace from JSON. Useful for reducing file size when transmitting data in APIs or storing in databases.
All JSON processing happens locally in your browser using JavaScript's built-in JSON.parse() and JSON.stringify(). Nothing is sent to any server.
Frequently Asked Questions
Common issues: trailing commas (e.g. [1,2,]), single quotes instead of double quotes, unquoted keys, missing colons or commas, and comments (JSON does not support comments). Our validator will identify the line and position of the error.
JSON is a text-based data format derived from JavaScript object syntax, but it is stricter. JSON requires double-quoted string keys, does not allow trailing commas, undefined values, functions, or comments. JavaScript objects are more permissive and exist in memory.
This browser-based tool handles JSON up to a few megabytes comfortably. For very large files (10MB+), consider command-line tools like jq (Linux/Mac) or Python's json.tool module, which stream data without loading it all into browser memory.