JSON Formatter

What is a JSON Formatter?

A JSON formatter takes a JSON document and rewrites it with consistent two-space indentation and one key or value per line, so you can read its structure at a glance. It works by parsing the text into a value and printing that value back out, which means your data is preserved exactly: only whitespace changes, never the keys, types, numbers, or strings themselves.

Alongside the editor, the page reports live statistics — total characters, characters excluding whitespace, lines, and the number of nodes — and offers a Tree View that renders the document as a collapsible structure, which is often faster to scan than raw text for deeply nested payloads.

How to Format JSON Online

• Paste your JSON into the input editor on the left. It highlights as you type and shows line numbers, so long payloads stay navigable.
• Press Format, or use the Ctrl+Enter (Cmd+Enter on Mac) shortcut. Output refreshes automatically a moment after you stop typing.
• Read the result in the output panel, which has its own line numbers and horizontal scrolling.
• Copy the output, or download it as formatted.json.

Two optional switches reshape the output as it is printed. Sort keys orders object keys alphabetically at every level, which produces a stable diff between two versions of the same document. Remove nulls strips properties whose value is null. If you have nothing handy to paste, Load example drops in a ready-made document.

Format vs Minify JSON

The two buttons produce the same document in different shapes, and you can switch between them at any time without re-pasting it.

• Format pretty-prints with two-space indentation. Use it when you are reading, reviewing, or debugging a payload.
• Minify collapses the document onto a single line with no optional whitespace. Use it to shrink a payload before sending or storing it, and compare the character count against the formatted size to see what the whitespace was costing.

JSON Formatter vs JSON Validator

Both tools parse your JSON strictly, so this page will refuse to format a broken document and report the line and column of the first problem it finds. The difference is the job each one does afterwards. Formatting reshapes a document that is already valid; validating is for diagnosing and confirming.

When you need a verdict rather than a cleaner layout, use the JSON Validator. It classifies the failure — a trailing comma, unquoted key, malformed number, and so on — explains the cause in plain language, offers a repair hint, shows the surrounding line of code, and summarises the document's root type, size, and depth.

Formatting API Responses

API responses usually arrive as one long line in browser developer tools or a terminal. Pasting that body here and pressing Format turns it into an indented document, and the Tree View lets you expand only the branch you care about. This is the quickest way to see which fields an endpoint actually returns, whether an id arrives as a number or a string, or where an unexpected null is hiding in a nested object.

To check how a response changed rather than read one in isolation, put a saved baseline in one side of the JSON Compare tool to get a path-by-path diff. To build types from the structure you just confirmed, hand it to JSON to TypeScript. If the call itself failed, HTTP Status Code Lookup explains what the returned code means.

Is JSON Uploaded to TechFixGen?

No. JSON processing happens locally in your browser — the document is parsed, formatted, sorted, and minified in the page itself, and the text you paste is not uploaded to TechFixGen servers. Your document is not written to the URL or to browser storage, so reloading the page discards it. Copy writes to your clipboard only when you click it, and Download saves a file that your browser generates on your own machine.

Common JSON Formatting Errors

Most documents that fail to format fail for one of a handful of reasons. Each one is reported with the exact line and column, and marked in the input editor's gutter so you can spot it without counting characters.

Trailing commas

A comma before a closing } or ] is invalid JSON. Remove the last comma in the object or array.

Single quotes and unquoted keys

JSON requires double quotes on every key and string. {name: 'Ada'} must become {"name": "Ada"}.

Comments

JSON has no comment syntax, so // and /* */ lines are rejected. Strip them before formatting.

Missing colon or comma

Every property needs a : after its name, and every pair of properties needs a , between them.

Literal newlines inside strings

A raw line break cannot appear in a string. Use \n, or let the formatter show you where the string was left open.

Malformed numbers

Leading zeros (01), trailing decimal points (1.), and values like 1,000 are not valid JSON numbers.

Non-JSON literals

Python and JavaScript spellings such as True, False, None, undefined, and NaN are rejected — JSON accepts only true, false, and null.

Extra data after the document

Two documents pasted one after another, or a stray HTML error page, fails at the point where the first document ends.