JSON Formatter & Viewer Online
Format and validate JSON, explore a collapsible tree, search keys and values, compare structures, and export conversions. Your JSON stays in your browser.
Written by Anil Gautam · Updated
Format JSON and inspect nested data
Paste an API response or upload a JSON file, then choose two spaces, four spaces or tabs and select Validate & Format. The tree view separates objects, arrays and primitive values; Expand all and Collapse all help navigate nested structures. The table view displays arrays of objects.
For {"user":{"id":7,"active":true}}, formatting adds indentation while the tree lets you expand user and inspect id and active individually. Formatting cannot make an invalid document valid; the status panel shows parsing errors before you use a data view.
Search, query, compare and export
Search finds matching keys and values with their paths. Query supports property access, array indexes, wildcards and recursive key lookup; it is a JSONPath-style subset. Diff compares parsed structures, so different object-key order alone is not a change. Array positions remain significant.
Convert provides minified JSON, CSV, YAML, XML, SQL, Markdown and escaped strings. These are convenience conversions: inspect generated SQL before running it, and check nested data when exporting flat tables. Repair applies best-effort syntax fixes; always review its output against your source.
JSON precision and import limits
This toolkit uses JavaScript JSON parsing. Integers beyond JavaScript's safe range and high-precision decimals may lose precision. Store identifiers as strings or use a lossless parser for exact financial or scientific values. Standard JSON does not support comments, trailing commas or undefined.
File imports are limited to 5 MB. Deeply nested or very large pasted documents may exceed browser memory or recursion limits. JSON contents are processed locally; uploaded files here are read by the browser rather than sent to a server.