JSON Formatter & Validator
Format, validate, beautify and minify JSON entirely in your browser. No uploads, no tracking — your data stays on your device.
Paste JSON, drop a file, or click Open file.
Result appears here. Everything runs in your browser.
Private by design
All formatting, validation and minification runs locally in your browser. Your JSON is never sent to a server.
Instant feedback
Get parse errors with line and column information, plus the surrounding context so you can fix typos in seconds.
Format, minify and sort
Pretty-print JSON with 2, 4 or tab indentation, minify for transport, and optionally sort object keys alphabetically.
Related conversion tools
Need to convert JSON to another format? Use one of the dedicated converters below.
Frequently asked questions
Is this JSON formatter really free? ▾
Yes. The Convertr.org JSON formatter, validator and beautifier is 100% free with no signup, no watermark and no usage limits.
Is my JSON uploaded to a server? ▾
No. This is a browser-native JSON formatter. Your JSON text never leaves your device — formatting, validation and minification all run locally in your browser using JavaScript.
What does the validator check? ▾
The validator checks that your input is syntactically valid JSON according to the official JSON specification. Errors include misplaced commas, unbalanced brackets, unquoted keys and trailing characters, with line and column information when available.
What is the difference between Format and Minify? ▾
Format (also called Beautify or Pretty Print) adds line breaks and indentation so the JSON is easy to read. Minify removes all unnecessary whitespace to make the JSON as small as possible for transport over the network.
Can I sort keys alphabetically? ▾
Yes. Enable the Sort keys option to recursively sort object keys alphabetically. Arrays preserve their original order.
How large a JSON file can I format? ▾
Because everything runs in your browser, the practical limit depends on your device. Modern desktops comfortably handle JSON files of several megabytes. For very large files, prefer command-line tools like jq.
Does this tool support JSON5 or JSONC (JSON with comments)? ▾
No. To stay strictly compliant with the JSON specification, JSON5 and JSONC (JSON with comments or trailing commas) are not supported. Remove comments and trailing commas before pasting.
Can I convert JSON to YAML, XML or CSV? ▾
This page focuses on formatting, validation and minification of JSON itself. For format conversion (JSON to YAML, JSON to XML, JSON to CSV), Convertr.org offers dedicated converter pages.