JSON Formatter
Format, validate, and minify JSON instantly.
How to use the JSON Formatter
Paste any raw, minified, or poorly-indented JSON and get clean output in one click. The validator catches syntax errors before you spend time debugging them.
- 1
Paste your JSON
Copy your raw or minified JSON — from an API response, a config file, or a server log — and paste it into the input box. The tool accepts any valid JSON object or array.
- 2
Format or Minify
Click Format to convert the JSON into readable, 2-space-indented output. Click Minify to strip all whitespace and compact to a single line — useful for reducing API payload size.
- 3
Validate without transforming
Click Validate to check whether the JSON is syntactically correct without reformatting it. The status bar shows the exact error and position if the JSON is malformed.
- 4
Copy the output
Click Copy Output to copy the result to your clipboard, then paste it directly into your editor, API client, or config file.
Frequently asked questions
What is JSON?
JSON (JavaScript Object Notation) is a lightweight text-based format for exchanging structured data between applications and servers. It represents data as key-value pairs, arrays, nested objects, strings, numbers, booleans, and null. Despite the "JavaScript" name, JSON is language-independent and natively supported by virtually every programming language.
What is the difference between formatting and minifying JSON?
Formatting adds indentation and line breaks to make JSON human-readable — ideal for reading API responses or debugging configs. Minifying removes all whitespace to produce the smallest possible string — useful when sending JSON over a network. Both represent exactly the same data; the difference is purely cosmetic.
Why does my JSON fail to validate?
Common reasons: trailing commas after the last item (valid JavaScript, invalid JSON), single-quoted strings instead of double-quoted, unquoted property keys, or // comments. The error message in the status bar points to the exact character where the problem occurs.
Is my JSON data safe to paste here?
Yes. All processing happens entirely in your browser using the built-in JSON.parse() and JSON.stringify() functions. Your data is never sent to any server. Open your browser's Network tab while using the tool — you will see zero requests made during formatting or validation.
Can this handle large JSON files?
Yes, for most real-world use cases. The tool handles JSON up to several megabytes without issue. Very large files (50 MB+) may be slow because processing runs on the browser's main thread. For extremely large files, a command-line tool like jq is more suitable.
What is the difference between JSON and JSON5?
JSON5 is a superset of JSON that allows comments, trailing commas, single-quoted strings, and unquoted keys — convenient for hand-written config files. Standard JSON (RFC 8259) allows none of these. This formatter validates standard JSON only. If your input uses JSON5 features, it will fail validation here.
Can I format JSONL (newline-delimited JSON)?
JSONL is a format where each line is a separate, complete JSON value. This tool formats one JSON document at a time. To format JSONL, paste and format each line individually. Pasting all lines at once will fail validation because the whole block is not a single valid JSON document.