JSON Formatter

Input JSON

400px

About This Free JSON Formatter & Validator

A lightning-fast, browser‑side JSON formatter, validator, & fixer. Paste or edit your JSON—no signup or server upload necessary. With the click of a button it will automatically pretty‑print, highlight syntax, detect mistakes, and even auto‑repair common issues—making it ideal for both devs and non‑technical users who want readable, valid JSON instantly (JSON formatter and JSON validator keywords available)

🚀 Key Features

  • Beautify / Prettify JSON with customizable indentation (2‑space, 4‑space, tab, compact)
  • Instant validation & linting for syntax errors and wrong data types
  • Fixes invalid JSON like missing quotes, trailing commas, wrong booleans/nulls
  • Copy to clipboard or download as .json file with one click
  • 100% client‑side: fast, private, works offline across modern browsers

🛠 Auto‑Fix Support

  • Adds missing double quotes around object keys
  • Converts single quotes to valid double quotes for JSON
  • Removes trailing commas in arrays or objects
  • Normalizes capitals in booleans & null (e.g., True → true, None → null)
  • Escapes control characters and invalid Unicode

Whether you're debugging API responses, cleaning minified JSON, or fixing malformed data from logs—this tool is your free go‑to JSON beautifier, syntax checker, and error fixer rolled into one. Optimized for SEO with keywords like "JSON formatter", "JSON validator", "JSON beautify online", and "fix JSON errors". Page loads fast and ranks well for JSON‑tool searches.