JSON Formatter & Minifier

Format JSON with proper indentation, minify it to a single line, or validate syntax — all instantly in your browser. No data is sent to any server.

Indent:

Input JSON

Output

Output will appear here...

When to format vs. minify JSON

Format — use during development when readability matters: debugging API responses, reviewing config files, or sharing JSON with teammates.
Minify — use in production to reduce payload size in API responses, config files, or when embedding JSON in code. Removing whitespace can cut file size by 20–40%.
Validate — use to quickly check if a string is valid JSON before passing it to JSON.parse().

Use with Claude

Claude frequently works with JSON — in tool calls, API responses, and structured outputs. Use this formatter to clean up Claude's JSON output before passing it to your application, or to format JSON before including it in a prompt for better readability.