JSON Formatter

Why I Built This JSON Formatter

I got tired of squinting at minified API responses in my browser's network tab. So I built this formatter to paste JSON and instantly see what's actually in there. Now I use it probably 10 times a day when debugging APIs or reviewing config files.

Features I Actually Use

Instant Validation - I can see immediately if my JSON is broken, which saves me from debugging the wrong thing
Beautify - One click to make any mess readable
Minify - When I need to paste JSON into a URL or config, this shrinks it down
Custom Indentation - I prefer 2 spaces, but 4 spaces for some projects
Sort Keys - Super useful for comparing objects or making configs consistent
Statistics - Helps me understand the structure at a glance: how many keys, nested objects, total size

I often use this alongside the YAML to JSON Converter when switching between config formats, and the URL Encoder when embedding JSON in API requests.

What is JSON?

JSON (JavaScript Object Notation) is probably the most common data format I work with. It's human-readable (when formatted) and machines parse it easily. I use it for:

API responses and requests
Configuration files (package.json, tsconfig.json)
Data storage and transfer
Basically everything in modern web development

The format is defined in RFC 8259 and maintained at json.org.

How I Use This Daily

Honestly, debugging API responses is where I use this most. When a request fails, I copy the response from DevTools, paste it here, and immediately see the structure. It's saved me hours of staring at minified text trying to find a missing field.

I also use it for config files. When reviewing pull requests that touch package.json or tsconfig.json, I format both versions and compare them. Consistent indentation makes diffs so much cleaner. DevOps folks on my team use it for Kubernetes manifests and cloud provider configs too.

When working with test fixtures or mock data, I always run them through here first. Nothing worse than a test failing because of a trailing comma or mismatched bracket.

API Debugging - My Workflow

Here's how I debug API issues: I grab the raw response from the Network tab (or cURL output), paste it here, and look for problems. Missing auth tokens in error responses, wrong pagination data, malformed nested objects - they all become obvious once the JSON is properly formatted.

For webhook debugging, I format incoming payloads to check if the structure matches what I expect. When integrating with Stripe, GitHub, or Slack webhooks, I paste the payload here to find specific fields like event types or timestamps. And when an API updates, I use the Diff Checker to compare old vs new response formats side by side.

Frequently Asked Questions

Is my JSON data secure?

Yep, everything runs in your browser. I built it this way because I paste production data here myself. Nothing ever leaves your machine.

What causes JSON validation errors?

In my experience, these are the usual suspects:

Missing or extra commas (the most common one)
Unquoted property names - JSON requires double quotes
Single quotes instead of double quotes (JavaScript habit)
Trailing commas after the last item (ES6 allows this, JSON doesn't)
Missing closing brackets or braces

Why should I minify JSON?

Minifying removes whitespace, which shrinks file size. I use it when:

Embedding JSON in URLs or query parameters
Reducing payload size for API requests
Storing JSON in databases where every byte counts