JSON Formatter & Validator

A fast, client-side JSON formatter and validator. Clean messy JSON, validate syntax with exact error positions, and minify payloads for production use. Zero data leaves your browser.

Indent:

Input (Paste raw or unformatted JSON)0 chars

Formatted Result0 chars

Key Capabilities

Prettify with customizable 2-space or 4-space indentation

Minify JSON for compact network payloads

Precise error highlighting with syntax messages

Copy to clipboard with one click

100% client-side: Zero data is transmitted to any server

Frequently Asked Questions

Is my JSON data uploaded to a server?

No. This tool runs 100% inside your browser using JavaScript. No network requests are made with your data.

Can this tool validate large JSON files?

Yes, it handles large JSON files up to several megabytes smoothly within your browser memory.

More Developer Utilities Tools

Base64 Encoder & Decoder

Encode plain text to Base64 or decode Base64 strings to UTF-8 text in real time.

UUID / GUID Generator

Generate cryptographically secure RFC 4122 Version 4 UUIDs in bulk.

URL Encoder & Decoder

Encode and decode URI components and query strings compliant with RFC 3986.