OpusDesk Hub What this tool does
JSON.parse checks syntax, then JSON.stringify formats the parsed value with indentation or compact spacing. Output is plain text, not syntax highlighting. Parser errors depend on the browser and do not always include a precise line number.
How to use JSON Formatter
- Paste JSON. Paste the complete JSON value, without comments or trailing commas.
- Choose formatting. Select Format or Minify. Parser errors appear instead of output for invalid syntax.
- Inspect and copy. Review the plain-text output and use Copy; there is no file-download control in this component.
Format and Validate JSON Privately
The JSON formatter beautifies, validates, and helps debug JSON data in your browser. It is a safer workflow for API payloads, configuration snippets, and logs that may contain internal data.
JSON Formatter vs JSON Validator
Formatting makes JSON easier to read with indentation and line breaks, while validation checks whether the structure is valid. This tool supports both workflows so developers can inspect data faster.
Common Developer Use Cases
Use the formatter when reviewing API responses, cleaning minified JSON, preparing examples for documentation, or locating syntax errors before pasting data into code or test fixtures.
How this tool works
The formatter parses input with the browser's JSON parser and serializes the resulting value with consistent indentation. Parsing errors are shown instead of guessing how malformed data should be repaired.
- Engine: Native JSON.parse and JSON.stringify
- Supported input: valid JSON object, array, string, number, boolean, or null
- Output: indented JSON text, validation error
Worked example
Input: {"user":{"id":7},"active":true}
Output: An indented JSON object preserving numeric user.id = 7 and boolean active = true
Limits, edge cases, and troubleshooting
Use it for API responses, configuration snippets, and test fixtures. A syntax error near the end often comes from a missing quote, bracket, or comma earlier in the document.
- The full document must fit in browser memory.
- Comments, trailing commas, NaN, Infinity, and JavaScript object literals are not valid JSON.
When to use another workflow
Use jq or an IDE for very large files, streaming data, schema validation, or repeatable transformations.
| Option | Best for | Trade-off |
|---|---|---|
| This browser tool | Quick, private, one-off work | Limited by browser memory and the documented feature set |
| Desktop or command-line tool | Batch jobs and repeatable automation | Requires installation and setup |
Supported inputs and limits
- valid JSON object, array, string, number, boolean, or null
- The full document must fit in browser memory.
- Comments, trailing commas, NaN, Infinity, and JavaScript object literals are not valid JSON.
Frequently asked questions
Does this validate my data schema?
It checks JSON syntax, not an application schema, duplicate-key policy or business meaning. JavaScript number precision applies.
Is the output syntax highlighted?
No. The current output is plain text with indentation; parser error wording varies by browser.
Is information sent to a server?
Tool inputs are processed in this browser. This product does not use analytics or send your input to an external API. Clicking an external website link still visits that website.