JSON (JavaScript Object Notation) is the de-facto data-interchange format powering virtually every modern web API. It’s human-readable—using braces, brackets, and key/value pairs—yet compact enough for efficient network transfers. Even so, unformatted “one-liner” JSON can be impossible to parse at a glance, especially when you’re debugging a complex API response or collaborating with teammates.

Pretty-printing JSON not only helps you catch syntax errors faster but also makes your data structures much more readable. When your JSON is neatly organized with proper indentation, collaboration becomes seamless: code reviews, documentation, and debugging sessions all benefit. This tool lets you validate, auto-fix, format, copy, download, or share your JSON—all locally in your browser. Paste your JSON below and click “Validate & Pretty Print” to get started instantly—no uploads, no servers, and total privacy.

Common issues include trailing commas, unescaped characters, and excessively large payloads. Our built-in repair engine can fix many of these problems automatically. Give it a try and save yourself time and frustration—whether you’re a seasoned developer or just experimenting with APIs for the first time!