JSON Formatter & Validator

Everything runs in your browser, so there are no ads, no trackers and nothing uploaded. On top of formatting and validation you get a collapsible tree view, one-click JSONPath copy, conversions to YAML, XML, CSV, a TypeScript interface and a JSON Schema skeleton, plus error locations pinpointed to the exact line and column. Open your network panel while you use it — the only request is the page itself.

Yes, within your device’s memory. Formatting and validation are fast for typical payloads (well under a megabyte) and stay responsive into the low single-digit megabytes on a modern laptop. Very large documents — tens of megabytes — may make the tab sluggish, especially in tree view, because the whole structure is held in memory. The text view copes better than the tree for huge inputs.

JavaScript object literals are more relaxed than the JSON specification. JSON forbids trailing commas, requires every key to be wrapped in double quotes, disallows single-quoted strings and comments, and does not allow values like undefined or NaN. Code that runs fine in a .js file can therefore be invalid JSON. The validator flags these, and offers quick-fixes for the two most common cases: trailing commas and unquoted keys.

A JSONPath is a string that locates a value inside the document, for example $.order.customer.name or $.items[0].sku. In tree view, click any key and its JSONPath is copied to your clipboard, ready to paste into code or a query tool. Use the chevrons to expand or collapse nodes and the search box at the top to filter the tree to matching keys or values.

No. The formatter, validator, tree view and every conversion run entirely on this page using native browser APIs. There is no upload endpoint, and your JSON never leaves your device. The optional History panel stores recent inputs only in your own browser (IndexedDB) and you can clear it at any time.

Yes. The Share button encodes your input into the URL hash — the part after the # — and copies the link. Because the data lives in the hash, it is never sent to our server; the browser keeps it client-side. When your colleague opens the link, the editor is pre-filled with the same JSON. Very large inputs make for very long URLs, so Share is best for small to medium snippets.