JSON toolkit

JSON, finally tamed.

Format, diff, validate and generate Schema from sample — without ever leaving the browser or pasting JSON into sketchy free tools.

See plans How it works

Plans from $5/mo — cancel any time

Paste JSON

Formatted / Diff / Schema

Everything a backend team paste-debugs

Built for engineers wiring up APIs, debugging webhooks, and reading 5 MB JSON dumps.

Lightning-fast format

Pretty-print or minify multi-megabyte JSON without freezing the tab. Tree view, line numbers, fold by key.

Two-payload diff

Paste two JSON blobs side-by-side — JSONForge highlights every added, removed, or changed key. Works on deeply nested structures.

JSON Schema validator

Paste a schema + a payload. Pass / fail / per-property errors. Supports JSON Schema draft 2020-12.

Schema from sample

Drop a sample JSON. Get a clean JSON Schema you can paste into your API spec or backend validation library.

Path query

JSONPath / JMESPath built in. Test selectors on real data before you ship them to production.

Private by design

Everything runs in your browser. Your JSON never touches a server unless you choose to save it.

Three steps

From a wall of JSON to a clean view of what changed or what failed.

Paste

Drop in your JSON — single payload or two for diff.

Pick a tool

Format, validate, diff, or generate Schema.

Ship

Copy the result straight into your code or your docs.

Simple pricing

Pick a plan and stop pasting into random websites.

Starter

For solo backend engineers

$5/mo

200 saved documents / mo
Full format, diff, validate
Schema from sample (500/mo)
Unlimited path queries

Frequently asked

Does my JSON leave my browser?

No. Format / diff / validate / Schema-from-sample all run client-side. Only saved documents (opt-in) are persisted server-side.

How big a payload can it handle?

Comfortably 10–20 MB on modern laptops. We stream-parse so the tab stays responsive even on huge files.

Which Schema draft do you support?

JSON Schema 2020-12 plus backward-compat with draft-07 and draft-06. We mark unsupported keywords clearly in the validator output.

Do I get a free trial?

No — this is a paid tool with plans from $5 a month. Starter is $5/mo and Pro is $15/mo; you can cancel any time.

How do I cancel?

From the account page, or by emailing us. Cancellation stops the next renewal — your remaining time stays usable.

JSON errors, explained

The message your parser just printed, the smallest input that causes it, and the corrected document.

Stop pasting JSON into random tools.

Format, diff, validate, ship.

See plans