JSONCraft is a free online JSON toolkit for developers. Format, validate, minify and diff JSON. Convert JSON to TypeScript interfaces, YAML, CSV and JSON Schema. Run JSONPath queries. No signup required — everything runs entirely in your browser. Your data never leaves your device.
$.users[?(@.age > 30)].email
Go to jsoncraft.in, paste or type your JSON and click Format (or press Ctrl+Shift+F). JSONCraft prettifies your JSON instantly with proper indentation. No signup, no limit.
JSONCraft validates your JSON in real time as you type. Syntax errors are underlined at the exact line and column. The status bar at the bottom shows Valid JSON or the specific error message.
Click Convert → JSON → TypeScript. Paste your JSON object or array and TypeScript interfaces are generated instantly. Optional fields are inferred when array items have different shapes.
Click Convert → JSON ↔ YAML. Paste JSON on the left, get YAML on the right. Switch direction to convert YAML back to JSON. Works with complex nested structures.
Click Convert → JSON ↔ CSV. Paste a JSON array of objects and get a CSV you can open in Excel or Google Sheets. Nested objects are flattened as parent.child column names.
parent.child
JSONPath is a query language for extracting data from JSON, similar to XPath for XML. Example: $.store.books[?(@.price < 10)].title selects titles of books under $10. Use the JSONPath Playground on JSONCraft to test expressions interactively.
$.store.books[?(@.price < 10)].title
Click Convert → JSON Schema. Paste your JSON and a JSON Schema Draft 7 definition is inferred automatically — including required fields, property types and nested object structures.
Click the Diff tab. Paste the first JSON on the left and the second on the right. Differences are highlighted and listed with path, old value and new value.
JSONCraft is 100% free — no account, no API key, no rate limits. It is fully privacy-first: all processing runs in your browser. Your JSON is never sent to any server.