— Data & developer

JSON Formatter & Validator

Paste JSON to beautify or minify it, validate the syntax, and pinpoint errors — instantly and entirely in your browser.

Drop a file here or click to choose — it never leaves your browser
— What it does

The JSON Formatter & Validator is a free tool that pretty-prints, minifies, and validates JSON entirely in your browser. Paste any JSON to reindent it with 2 spaces, 4 spaces, or tabs, collapse it to a single line, optionally sort object keys, and get an exact error message with the line and column when the syntax is invalid.

  • Beautify with 2-space, 4-space, or tab indentation, or minify to one line.
  • Live validation with the exact error message plus line and column position.
  • Optional alphabetical key sorting and a key and size summary.
  • Runs entirely in your browser — your JSON is never uploaded to a server.

How to use it

1

Paste your JSON

Paste any JSON object or array (or drop a .json file) into the input box.

2

Choose format and indent

Switch between Beautify and Minify, pick 2 spaces, 4 spaces, or tab, and toggle sort keys.

3

Copy or download the result

The formatted JSON and validation status update as you type. Copy it or download a .json file.

Frequently asked

Is my JSON uploaded anywhere?
No. Formatting and validation run entirely in your browser with JavaScript. Your data is never sent to a server, so it is safe for sensitive or proprietary JSON.
What does the validator check?
It parses your input with the browser JSON engine, so it catches every syntax error — missing commas, trailing commas, unquoted keys, unbalanced brackets — and reports the message with an approximate line and column.
What is the difference between beautify and minify?
Beautify re-indents JSON across multiple lines so it is easy to read and diff. Minify removes all optional whitespace to produce the smallest valid JSON for transport or storage.
What does sort keys do?
Sort keys reorders every object property alphabetically at all nesting levels. It is useful for producing stable, diff-friendly output when comparing two JSON documents.

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← All free tools

— Built by saavos

These tools are free. So is the first version of your agent.

saavos is the AI agent that lives on your website — themed to match your design, answering visitors from your own content, and telling you what they actually want to know. Paste your URL and see it answer, before you install anything.

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