Json Formatter
Online json formatter tool by 4TBOX.
Json Formatter
Online json formatter tool by 4TBOX.
Paste your JSON on the left, click Format JSON or Minify, and get a clean result on the right. Ideal for debugging API responses, logs and configuration files.
Tip: paste JSON and press Ctrl / ⌘ + Enter to pretty-print.
Turn JSON Formatter into a proper debugging workstation.
PRO will add AI-powered fixes, JSON diff, schema validation and export options — without removing anything from the free version.
- Auto-fix malformed JSON with a single click
- Compare two JSON payloads side-by-side (diff view)
- Validate against schemas & generate types
- Export formatted JSON to files and snippets
PRO is optional. Free tools stay free — PRO simply adds more firepower for people who need it.
Learn more about 4TBOX PROWhat is a JSON formatter?
A JSON formatter is a small utility that takes raw JSON and makes it easier to read. It adds indentation, line breaks and consistent spacing so you can quickly understand the structure of an object. It is especially useful when you are working with API responses, logs or configuration files that come in a single long line.
How to use this JSON formatter
- Paste or write your JSON in the input panel on the left.
- Choose the indentation size you prefer (2 or 4 spaces) using the Indent buttons.
- Click Format JSON or press Ctrl / ⌘ + Enter.
- The formatted JSON will appear in the Result panel.
- If you need a compact version, click Minify instead.
Is this JSON formatter secure?
Yes. Everything happens in your browser. Your JSON is never sent to any server and never leaves your device. This makes the tool safe to use with sensitive payloads, internal APIs or development data, as long as you follow your own security policies.
Common use cases
- Inspecting and debugging JSON responses from APIs.
- Pretty-printing JSON logs during development.
- Cleaning up configuration files before committing them.
- Sharing readable examples of JSON with teammates.
Frequently asked questions
What happens if my JSON is invalid?
If the JSON cannot be parsed, you will see an error message below the editor indicating what went wrong. Fix the issue in the input panel and run the formatter again.
Can I use this tool for very large JSON files?
The formatter runs entirely in your browser, so very large JSON files may feel slower depending on your device. For most API responses and typical development tasks it should work smoothly.
Does 4TBOX offer more JSON tools?
Yes. 4TBOX is a full toolbox of online utilities for developers and creators. You will find additional JSON tools, text helpers, encoders/decoders and AI-powered assistants in the main catalog.