Format JSON Online, Free JSON Formatter & Validator
Beautify messy JSON, minify it back down, or validate and find the exact error.
How to format json
To format JSON, paste it into a JSON formatter and choose beautify to add consistent indentation and line breaks, or minify to strip whitespace for the smallest possible payload. A validator parses the input and pinpoints the line and character of any syntax error: a missing comma, an unquoted key, a trailing bracket. Related developer tools convert JSON to CSV/YAML, diff two documents, and generate TypeScript types. GigAI's JSON tools run entirely in your browser, so config files, API responses and payloads never leave your machine.
5 tools for this task
Every one is free, private and runs in your browser. No sign-up.
JSON Formatter
Format, validate and minify JSON in your browser with pinpoint error line + column, jump-to-error, key sorting and live editing: nothing is uploaded.
JSON Validator
Validate JSON against RFC 8259 with the exact error line, column and a caret under the bad character. Get plain-English explanations, one-click auto-fix for trailing commas and single quotes, plus depth, key-count and type stats, nothing uploaded.
JSON Tree Viewer
Explore JSON as an interactive, collapsible tree. Expand or collapse any branch, see type and array-length badges, search keys and values with live highlighting, and copy any node's value or its JSONPath in one click, all 100% in your browser.
JSON Diff
Compare two JSON documents by structure, not text. Reordered keys and whitespace are ignored. You see added, removed and changed values by path with counts, all in your browser.
JSON to TypeScript
Convert JSON to TypeScript interfaces or types instantly, with merged unions across array items, optional-from-null, readonly, export and naming controls, 100% in your browser.
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