Use JSON Validator online for free. No installation, no signup — works directly in your browser.
100% free, no signup required. Works entirely in your browser.
Open JSON ValidatorEnter the JSON you want to validate.
Get instant validation results.
See exact error locations and fix them.
The validator detects all JSON syntax errors including missing commas, unclosed brackets, unquoted keys, trailing commas, invalid escape sequences, and duplicate keys. Each error is reported with its exact line and column number, making it easy to locate and fix issues in large JSON documents.
Yes, you can validate your JSON data against a JSON Schema definition to ensure structural correctness. This verifies not just syntax but also data types, required fields, value constraints, and nested object schemas. It supports Draft-07 and later schema specifications.
The validator highlights the exact location of each error with descriptive messages so you can fix them manually and understand the root cause. For common issues like trailing commas or missing quotes, the error messages suggest the specific fix needed. This approach ensures you learn proper JSON syntax.
