JSON Formatter
Paste messy, minified, or broken JSON and get it reformatted with proper indentation, or run it through validation to get a precise error location when something's malformed. A one-click minify mode strips whitespace for production use.
How it works
- 1
Paste your JSON into the editor.
- 2
Click format to beautify, or minify to compress it.
- 3
If the JSON is invalid, see exactly where the syntax error is.
- 4
Copy the cleaned-up result to your clipboard.
What people use it for
- Making an unreadable one-line API response reviewable.
- Validating that a config file is well-formed JSON before deploying it.
- Minifying JSON before embedding it in a template or a query string.
- Finding the exact position of a syntax error in a payload someone sent you.
Supported formats & options
| Input | Any JSON text: objects, arrays, nested structures |
|---|---|
| Format | Two-space indented, human-readable output |
| Minify | All optional whitespace removed |
Key advantages & benefits
Clear error locations
Instead of a vague 'invalid JSON' message, see the line and character where parsing failed.
Format and minify both included
Switch between a readable, indented view and a compact, whitespace-free version for production.
Handles large payloads
Paste large API responses or config files without the editor lagging.
No data leaves your browser
Sensitive API tokens or internal payloads in your JSON aren't sent anywhere to be formatted.
Limits & things to know
- Strict JSON only. Trailing commas, comments, single-quoted strings and unquoted keys are invalid and will be reported as errors — that is the specification, not a limitation of the parser.
- Very large payloads (tens of megabytes) can make the tab sluggish, since the whole document is parsed and re-serialised in memory.
- Key order is preserved as written, but JSON objects are unordered by specification — do not rely on order for correctness.
Troubleshooting
Unexpected token error
Look for a trailing comma before a closing brace or bracket, a comment line, or smart quotes introduced by a word processor. All three are invalid JSON.
The payload has a BOM or stray characters at the start
A byte order mark from a Windows editor breaks parsing. Remove the leading invisible character, or re-save the file as UTF-8 without BOM.
Numbers change slightly
JSON numbers are parsed as IEEE 754 doubles. Very large integers, such as 64-bit IDs, lose precision — transmit those as strings.
Privacy & data handling
Parsing and formatting run entirely in your browser, so pasting a payload that contains tokens, customer records or internal identifiers does not send them anywhere.
Free Online JSON Formatter, Validator & Beautifier
This free online JSON formatter beautifies, validates and minifies JSON in a single pass, directly in your browser. Paste a raw API response, a package manifest or a broken config file and get properly indented, pretty-printed JSON back instantly — with the exact line and character of any syntax error called out instead of a generic failure message.
- Beautify JSON with one click — turn minified or single-line JSON into readable, indented output with consistent nesting, ideal for reviewing API payloads and configuration files.
- JSON validator with precise error locations — the built-in JSON syntax checker points at the missing comma, trailing bracket or unquoted key by position, so debugging a malformed payload takes seconds rather than a manual scan.
- Minify JSON for production — strip every byte of whitespace to shrink request bodies, config bundles and stored payloads before you ship.
- Handles large JSON files — multi-megabyte API responses, log exports and database dumps parse locally without an upload queue or a file-size paywall.
- 100% private — nothing is uploaded — parsing runs in your browser tab using the native JSON engine, so access tokens, customer records and internal payloads never touch a server.
No sign-up, no daily limit and no watermark. Bookmark it as your everyday JSON pretty printer, and pair it with the Data Converter when you need JSON to CSV, XML or YAML instead.
Frequently asked questions
What happens if my JSON has a syntax error?
The formatter highlights the specific location of the problem — like a missing comma or unclosed bracket — instead of just failing silently.
Can it handle very large JSON files?
Yes, though extremely large payloads (multiple MB) may take a moment longer to parse and render in the editor.
Does minifying remove comments?
Standard JSON doesn't support comments at all, so if your input has JSON5-style comments, they'll need to be removed before minifying.
Is my pasted JSON stored anywhere?
No — parsing and formatting happen locally in your browser tab and nothing is saved or transmitted.
Can I convert the formatted JSON to CSV?
Yes — for format conversion beyond beautifying, check out the Data Converter tool, which handles JSON-to-CSV and other formats.