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JSON Tools

JSON Beautifier Online

Turn minified or messy JSON into clean, indented, readable JSON.

Updated

Ctrl/Cmd + Enter to run

Formatting changes whitespace only. JavaScript parsing can change very large integer precision, collapse duplicate keys, or reorder integer-like keys, so keep the original input when exact preservation matters.

This tool runs in your browser. No account or signup is required.

Common JSON Beautifier tasks

Developers typically reach for this page when they need to beautify minified JSON online; expand one line JSON; make an API response readable. The tool is built for quick, practical work rather than a generic demo.

What matters in a json beautifier workflow

When developers compare online tools for this job, the useful capabilities tend to center on multiple indentation choices, upload, tree view, syntax errors. This page keeps those practical needs in mind while linking to related tools when a different workflow is a better fit.

What is JSON Beautifier?

JSON Beautifier re-prints JSON with 2-space indentation and one item per line, so nested objects and arrays are easy to follow.

What problem does it solve?

Logs, network panels and API clients often show JSON squeezed onto one line. Reading it that way hides the structure and makes mistakes easy to miss.

How to use JSON Beautifier

  1. Paste your JSON into the input box.
  2. Press Process.
  3. Copy the beautified result. If the JSON is invalid, you get the parser error instead.

Example

Input

{"user":{"id":1,"roles":["admin","dev"]},"active":true}

Output

{
  "user": {
    "id": 1,
    "roles": [
      "admin",
      "dev"
    ]
  },
  "active": true
}

What you can do with JSON Beautifier

  • Beautify JSON online
  • Pretty print JSON
  • Make minified JSON readable

Common use cases

  • Reading a minified response copied from browser dev tools
  • Making JSON diff-friendly before code review
  • Pasting readable JSON into documentation or a bug report

Related developer tasks

  • Beautify JSON online
  • Pretty print JSON
  • Make minified JSON readable

When to beautify JSON

  • Reading a minified response copied from browser dev tools or a log line
  • Making JSON diff-friendly so a code review shows one change per line
  • Putting readable JSON into documentation, tickets and bug reports
  • Checking nesting depth and spotting a misplaced bracket by eye

Beautified versus minified JSON

For ordinary JSON, beautified and minified output represent the same values. Beautified JSON adds line breaks and indentation for people; minified JSON removes unnecessary whitespace for compact storage or transport. JavaScript parsing can still normalize large numbers, duplicate keys and integer-like key order.

You can switch between the two for ordinary JSON, but this browser-based parser has the same JavaScript number, duplicate-key and integer-like-key behaviors described above.

Go the other way: JSON Minifier

Beautifier, formatter and pretty printer

These names describe the same operation. On this site the JSON Beautifier and the JSON Formatter use the same engine and the same 2-space indentation. Use whichever name you searched for. If you also want a clear valid or invalid verdict, use the JSON Validator.

Related: JSON Formatter, JSON Validator

JSON Beautifier FAQ

What makes JSON invalid?

Common causes are trailing commas, single quotes instead of double quotes, unquoted keys, and comments. Strict JSON allows none of these.

Does formatting preserve my JSON exactly?

Formatting changes whitespace, but this tool uses JavaScript JSON.parse and JSON.stringify. Very large integers can lose precision, duplicate object keys keep only the last value, and integer-like keys can be reordered. Keep the original input when exact preservation matters.

Is my data sent to a server?

The processing runs in your browser, so what you paste into the tool is not uploaded for processing. As with any tool, avoid pasting live secrets you cannot afford to leak.

Can I choose tabs or 4-space indentation?

Yes. The shared JSON tool supports 2 spaces, 4 spaces or tabs for formatted output.

Does beautifying change the order of keys?

Usually the existing order is retained, but JavaScript reorders integer-like object keys such as "1" and "2". Duplicate keys also collapse to the last value.

Is this different from the JSON Formatter?

No. Both produce the same output. They exist as separate pages because people search for both names.

Looking for something else? Browse all developer tools.

onlinedevelopertool.com is a collection of 54 free, browser-based utilities for the small jobs that interrupt real work: formatting a JSON response, decoding a token, converting a timestamp, generating a UUID or checking a hash. Each tool has its own page with a short explanation, a worked example and answers to common questions, so you can use it and learn what it does at the same time.

There is no account to create and nothing to install. Tools run in your browser, so the text you paste is processed on your own device. The one exception is the Website Status Checker, which sends a request from your browser to the address you enter.

Three steps: paste your input, click the tool, copy the result, all inside your browser
Popular developer utilities: JWT decoder, UUID generator, Base64 decoder, SHA-256 hash, regex tester and timestamp converter

What you can do here

  • JSON Tools

    Format, validate, beautify and minify JSON, generate C#, TypeScript, Java, Python, Go, PHP and Kotlin models from it, or convert between JSON, YAML and CSV.

  • Encoders & Decoders

    URL, Base64 and HTML encoding and decoding, plus a JWT decoder for reading token claims.

  • Generators & Hashes

    Generate UUIDs and JWTs, validate UUIDs, and create MD5, SHA-256 and SHA-512 hashes.

  • Web Tools

    Timestamps, color codes, query strings and cron expressions - the small things web work keeps throwing at you.

  • Text & Data

    Format XML and YAML, count text, change case, make slugs, test regex, diff two texts and convert number bases.

  • Website Checking

    Check whether a website or URL is reachable from your browser.

Quick developer reference

  • JSON

    Keys and strings must use double quotes, and trailing commas and comments are not allowed. Those are the three most common reasons a payload fails to parse.

    Validate JSON

  • JWT

    A JSON Web Token is three Base64URL parts joined by dots: header, payload and signature. Decoding shows the claims but does not prove the token is genuine; only signature verification does.

    Decode a JWT

  • Base64

    Base64 is an encoding, not encryption. Anyone can reverse it, and it makes data roughly one third larger, so never use it to hide secrets.

    Decode Base64

  • UUID

    A version 4 UUID is made of random bits and written as 8-4-4-4-12 hexadecimal characters. Collisions are astronomically unlikely, which is why they work well as identifiers.

    Generate a UUID

  • Timestamps

    A Unix timestamp counts time since 1 January 1970 UTC. Ten digits usually means seconds and thirteen digits usually means milliseconds.

    Convert a timestamp

  • Hashes

    MD5 is fine for quick checksums but is not safe for security. Prefer SHA-256 or SHA-512, and remember that hashing is one-way and is not encryption.

    Create a SHA-256 hash

Missing a tool you need? Visit the contact page and tell us what you reach for most often. You can also browse every tool or read the About page to see how the site is built and what it does with your data.