JSON Formatter
Pretty-print, validate or minify JSON instantly in your browser.
About the JSON Formatter
JSON is how systems talk to each other — API responses, configuration files, webhooks, exports — but machines emit it as a single unreadable line. This formatter turns that line into cleanly indented, human-readable structure in one click, or does the reverse: minifying a formatted document back to its most compact form for production payloads.
It's also a validator. The formatter parses your input with the same strict rules every JSON consumer uses, so if there's a problem — a trailing comma, single quotes instead of double, an unquoted key, a stray character — you get the parser's actual error message instead of a silent failure later in your pipeline. Fixing JSON here is much faster than deploying and reading a stack trace.
Formatting runs entirely in your browser: API keys, customer records and internal payloads never leave your machine, which is exactly what you want when debugging production data. Use 2-space indentation (the JavaScript ecosystem default) for reading and code reviews, 4-space when you'll be scanning deeply nested structures, and minify when every byte counts. A practical debugging loop: paste the response from your API client, format to inspect the structure, edit the value you're testing, then minify and send it back. The output downloads as a .json file when it's too large to comfortably copy.
Frequently asked questions
- Why is my JSON invalid?
- The usual culprits: trailing commas after the last item, single quotes instead of double quotes, unquoted property names, comments (JSON doesn't allow them), and smart quotes pasted from documents. The error message points at the position of the first problem.
- Is my JSON uploaded anywhere?
- No. Parsing and formatting run entirely in your browser with JavaScript's native JSON engine — safe for payloads containing keys, tokens or customer data.
- When should I minify JSON?
- For production traffic and storage: minified JSON strips all whitespace, cutting payload size meaningfully on large documents. Keep the pretty version for humans, ship the minified one to machines.
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