JSON Validator
Validate JSON instantly. Format or minify valid JSON safely in your browser.
About JSON Validator
A JSON validator is a utility that checks whether a JSON string is correctly formatted and can be parsed without errors. JSON is commonly used for APIs, configuration files, web applications, and data exchange between systems. Even small mistakes such as missing quotes, extra commas, or mismatched brackets can cause a JSON document to fail. A validator helps identify these issues quickly and reduces time spent debugging.
This tool validates JSON in the browser and provides clear output that indicates whether input is valid or invalid. It can also format JSON for readability or minify it for compact storage and transfer.
How JSON Validation Works
The tool parses the input using standard JSON rules. If parsing succeeds, the JSON is valid. If parsing fails, the tool reports an error message. In many cases, browsers provide a character position for the error, and the tool converts that into an approximate line and column to make debugging easier.
Options are included for common real-world cases where JSON is pasted from configuration files. Trailing commas and comments are not part of official JSON, but they appear in some environments. When enabled, the tool preprocesses input to remove comments and ignore trailing commas before validation.
Common Uses
JSON validation is used when testing API payloads, fixing configuration files, reviewing JSON exports, and preparing structured data. Developers use it to debug requests and responses. Analysts use it to confirm data integrity before importing into tools. It is also useful for formatting JSON for documentation and sharing.
Privacy and Browser-Based Processing
This tool processes JSON locally in the browser. Input is not uploaded, stored, or transmitted. No accounts, external services, or installations are required.
Frequently Asked Questions
1. Does this tool upload my JSON?
No. All processing happens locally in the browser.
2. Why does JSON validation fail when comments are present?
Standard JSON does not allow comments. Enable the comments option only if needed.
3. What are trailing commas?
A trailing comma is a comma placed before a closing } or ]. Standard JSON does not allow it.
4. Can the tool format JSON?
Yes. Pretty print formats JSON with indentation for readability.
5. Can the tool minify JSON?
Yes. Minify removes unnecessary spaces to create compact JSON output.