JSON Validator
Check whether JSON is syntactically valid and see the top-level data type and item count.
About JSON Validator
JSON Validator parses the submitted JSON with PHP’s native JSON parser and reports a precise syntax error when parsing fails. Valid input also reports whether the top level is an object, array or scalar.
How to use JSON Validator
Paste JSON into the editor and run the validator. ToolFlow parses the complete value and returns either a valid status or the parser error that needs to be corrected.
When JSON Validator is useful
- Check API payloads before sending them to an endpoint.
- Validate configuration snippets copied from documentation.
- Confirm that generated JSON can be parsed before saving or publishing it.
Practical tips
- A trailing comma is invalid in standard JSON.
- Object keys must use double quotes.
- Validate after every manual edit when working with large payloads.
JSON Validator FAQ
Does the validator modify my JSON?
No. It only parses the submitted text and reports whether it is valid.
Can it validate arrays and scalar JSON values?
Yes. Any syntactically valid JSON value can be checked.
Privacy and file handling
Submitted values are processed to produce the requested result. This tool does not require an external content-generation provider. Avoid submitting confidential information unless you are comfortable with the site's server and hosting retention policies. See the Preifatrwydd for details.