JSON Formatter with Parse Error Positions

What is a JSON formatter?

A JSON formatter takes raw JSON — often a single unreadable line copied from an API response, a log file, or a database record — and pretty-prints it with consistent indentation so the structure becomes visible at a glance. This tool also validates as it formats: if the input isn't legal JSON, you get the exact parser error instead of silently broken output.

Everything runs in your browser. The JSON you paste is never uploaded, stored, or logged, which makes it safe to format payloads that contain internal identifiers or customer data.

When to use it

Reach for a formatter whenever you're debugging an API response and need to find one field inside a wall of minified JSON, when you're writing configuration by hand and want to confirm it parses before deploying, or when a teammate sends you a payload and you need to talk about a specific nested value. The Minify option does the reverse — strips all whitespace — which is useful before embedding JSON in a URL, an environment variable, or a size-sensitive request body.

The validator is also the fastest way to hunt down the classic JSON mistakes: trailing commas, single quotes instead of double quotes, unquoted keys, and comments (JSON allows none of these). The error message points at the position where parsing failed, so you can fix it instead of guessing.

Example

Paste {"user":{"id":42,"name":"Ada","roles":["admin","dev"]}} and Format produces an indented tree where each key sits on its own line — with keys, strings, numbers, booleans and nulls color-coded. Switch the indent between 2 and 4 spaces to match your codebase's style, then copy the result or share it with the "Copy link to this result" button, which encodes your input into the link itself.