JSON & data

JSON formatter & validator

Pretty-print, validate, and explore any JSON — locally, in your browser.

JSON Diff tab · 7-day free trial · Premium $9.99 / yr

Try it now·runs locally · nothing uploaded

Input✓ valid

Output

{
  "id": 42,
  "name": "Alice",
  "tags": [
    "engineer",
    "admin"
  ],
  "address": {
    "city": "Oslo",
    "zip": "0150"
  }
}

Want side-by-side JSON diff, JSONPath, and instant access from any tab?Install free trial →

★ Premium

Built for the things AI can’t fake

This tool runs free, right here. The extension adds three things a web widget can’t:

Start 7-day trial→

★ Flagship

Playground

↗

JS / TS scratchpad — sandboxed and instrumented.

Paste real code, hit Run. Console + network monitor + watch expressions all in one panel.

·Real ES modules · top-level await
·URL imports — esm.sh & friends
·Live fetch monitor (every call)
·Watch expressions in your scope
·10s sandbox timeout · zero CORS pain

HTTP client

↗

Postman-style request runner.

Save collections, share variables, hit any API. Includes GraphQL with introspection, OpenAPI / cURL import.

·Bearer / Basic / API-key auth
·GraphQL · introspection
·OpenAPI 3.x · cURL import
·Copy as fetch / axios / Python

Realtime (WS + SSE)

↗

Stream-protocol tester — what Postman doesn’t do well.

WebSocket + Server-Sent Events with custom auth headers, auto-reconnect, JSON pretty-print.

·wss:// + ws:// + subprotocols
·SSE via fetch — Authorization works
·Auto-reconnect with backoff
·Send composer · ⌘ + Enter

What it does

A JSON formatter takes minified or messy JSON and rewrites it with consistent indentation, sorted keys, and proper line breaks. A JSON validator checks that the syntax is correct and tells you exactly where it isn’t.

VibeGear ships both in one panel: paste JSON on either side, see live red/green validity badges, hit Format and the document is pretty-printed in place. Both panes are editable so you can tweak as you read.

Why use VibeGear's json formatter & validator

✓Runs locally — your JSON never leaves the browser
✓Live validation as you type, with line numbers on errors
✓JSONPath inspector for "find the field I care about"
✓YAML → JSON conversion via a single button
✓Side-by-side diff with the matching JSON document

How to use it

1Open the JSON Diff tab (Alt+6) or the JSON Explorer tool.
2Paste your JSON into either pane.
3Click Format on the toolbar — both panes get pretty-printed.
4Use Minify to do the reverse, or copy the formatted output with the Copy button.

Example

Input

{"id":42,"name":"Alice","tags":["a","b"]}

Output

{
  "id": 42,
  "name": "Alice",
  "tags": [
    "a",
    "b"
  ]
}

Frequently asked

Is the JSON sent to a server?

No. Everything runs in your browser; we never see your input.

How big a JSON document can I paste?

Megabytes work fine. The Monaco editor handles large inputs without choking; only really gigantic blobs (100+ MB) start to feel sluggish.

Related tools

JSON validator

Validate JSON syntax with line-precise errors, instantly.

JSON explorer

Tree view for big JSON. Search, expand, copy paths.

JSON → TypeScript

Generate TypeScript interfaces from a JSON sample.

JSONPath tester

Run JSONPath expressions against any JSON, live.

YAML to JSON

Parse YAML into pretty JSON in one paste.

★ Premium

One install. Every tool above.

7 days free, then VibeGear Premium is $9.99 / €9.99 per year. Everything runs locally.

Install & start trial →→

Language

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