JSON Formatter

Format, beautify, validate and minify JSON instantly — in your browser, with line-and-column error reporting. Nothing is uploaded.

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100% free, no sign-up Runs in your browser — nothing uploaded Instant, works offline
What is JSON? Why the strict format? Formatting rules Base64 lessons

How Does the JSON Formatter Work?

Three steps, all in your browser.

1

Paste your JSON

Drop in an API response, a config file, or any JSON snippet — single-line or messy is fine. Try the sample chips if you just want to see it work. New to the format? Read what JSON is.

2

Format, minify, or validate

Pretty-print and beautify with 2-space, 4-space or tab indent, collapse it to the smallest payload with Minify, or just check it with Validate. Press Ctrl/Cmd + Enter to format without leaving the keyboard.

3

Fix errors fast

If the JSON is invalid, you get the exact line and column where parsing failed — so trailing commas and stray quotes are easy to spot. Want the rules? See JSON formatting rules.

Frequently Asked Questions

What does a JSON formatter do?
A JSON formatter takes raw, often single-line or messy JSON and pretty-prints it with consistent indentation and line breaks so it is readable. This tool also validates the JSON as it formats — if the text is not valid JSON, it tells you exactly where it breaks (line and column) instead of silently producing wrong output. It can also minify, stripping every optional space and newline to make the smallest possible payload.
Is my JSON sent to a server?
No. The formatter runs entirely in your browser using the native JSON engine. Nothing you paste is uploaded, logged, or stored — you can even use it offline once the page has loaded. That makes it safe for config files, API responses, and other data you would not want to send to a third-party site.
What is the difference between formatting and minifying?
Formatting (pretty-printing) adds indentation and newlines so a human can read the structure. Minifying does the opposite: it removes every optional whitespace character so the JSON is as small as possible for sending over a network or embedding in code. Both produce exactly the same data — only the whitespace differs, and whitespace is never significant in JSON outside of string values.
Why does my JSON say it is invalid?
The most common causes are a trailing comma after the last item in an array or object, single quotes instead of double quotes, unquoted keys, comments (JSON does not allow them), or a missing closing bracket or brace. Real JSON requires double-quoted keys and strings, no trailing commas, and no comments. This tool points to the line and column where parsing failed so you can find the offending character quickly. See the formatting rules for the full list.
Should I indent with 2 spaces, 4 spaces, or tabs?
It is purely cosmetic — JSON parsers ignore indentation entirely. Two spaces is the most common default for JSON and keeps deeply nested data from drifting too far right; four spaces is easier to scan; tabs let each reader pick their own width. Match whatever your project or team already uses. You can switch indent here and re-format instantly.
Do I need an account to use this JSON formatter?
No. There is no account, no login, and no payment. It is a free browser tool, and because all processing happens locally there is nothing to sign up for. Open the page and start formatting.