Format, minify, validate, and tree-view JSON instantly — runs entirely in your browser. No data sent to any server. Ever.
JSON (JavaScript Object Notation) is a lightweight text format for storing and exchanging data. It's human-readable, language-agnostic, and supported by every modern programming language. APIs, config files, and databases all use it.
JSON supports six types: string (text in double quotes), number (integers or decimals), boolean (true/false), null, object ({} key-value pairs), and array ([] ordered lists).
JSON is strict: keys must be in double quotes (not single), trailing commas are not allowed, and undefined is not a valid value. Use this validator to catch these issues instantly with exact line and column numbers.
Tree view is ideal when exploring large or deeply-nested JSON — API responses, config files, exported data. Collapse branches you don't need, expand only what matters. Size counts show item counts at a glance.