Is Prettify JSON free?

Yes. Every VersaTools tool is completely free — no account, no watermark, and no sign-up required.

Is my JSON uploaded to a server?

No. Parsing, formatting, and highlighting all run locally in your browser with the built-in JSON engine, so your data never leaves your device.

What does Sort keys do to arrays?

Nothing — arrays keep their original order. Sort keys only alphabetizes the keys inside objects, and it does so recursively at every level of nesting.

Why does it say my JSON is invalid?

The tool uses strict JSON rules, so trailing commas, single quotes, comments, and unquoted keys all fail. The error message and the line and column tell you exactly where to look.

Can it handle very large JSON?

Yes, within your browser's memory. Because nothing is uploaded, huge files simply use more local memory; formatting stays instant for typical payloads.

Prettify JSON

JSON & Data Serialization

Format, validate, and indent raw JSON into clean syntax.

Indent

Sort keys

Input

Formatted

Paste JSON on the left, or use Load sample. The formatted, color-coded result appears here instantly.

Tool Overview & Guide

What is Prettify JSON?

Prettify JSON validates, formats, and color-codes raw or minified JSON so you can actually read it. Paste a blob, pick an indent style, and see a clean, syntax-highlighted result instantly — or switch to Minified to strip every space for the smallest possible output. If the JSON is broken, you get the parser's message plus the exact line and column so you can fix it fast. Everything runs in your browser, so your data is never uploaded.

Technical Specifications & Supported Formats

Processing Engine:Client-side Native JavaScript & WebAssembly

Privacy & Security:100% In-Browser (Zero File Upload)

Supported Formats:All Standard Formats & Code Text

Max File Limit:100 MB

How to use Prettify JSON

3 simple steps to complete your task directly in your browser:

Paste your JSON
Drop raw, minified, or messy JSON into the Input box on the left. Or click Load sample to try it with a realistic example. Formatting happens live as you type.
Choose an indent style
Pick 2 spaces, 4 spaces, or Tab for pretty output — or Minified to collapse everything onto one line. The formatted, color-coded result appears on the right.
Sort keys if you want a canonical shape
Tick Sort keys to alphabetize every object's keys recursively (arrays keep their order). This is handy for diffing two objects or producing stable, comparable output.

Common uses

Make a minified API response readable while debugging
Validate that a config or payload is well-formed JSON before shipping it
Minify JSON to shrink a request body or config file
Alphabetize keys to produce a stable shape for clean diffs
Pinpoint the exact line and column of a syntax error
Reformat copied JSON to a consistent 2-space or tab style

Why choose VersaTools

100% private

Your files are processed inside your browser and are never uploaded to a server.

Free, no account

No sign-up, no watermark, no paywalled “premium” tier. Just open a tool and use it.

Instant

No upload, no queue, no server round-trip — work starts the moment you drop a file.

Runs in your browser

Built on open web standards. Works on any modern desktop browser, nothing to install.

No upload size caps

Nothing leaves your device, so there’s no server file-size limit — only your machine’s memory.

Yours to keep

Results download straight to your device in clean, standard file formats.