JSON Validator
Validate JSON data with detailed error messages and line-by-line analysis. Free online JSON validator and lint tool.
Examples
{
'name': 'FormatForge',
'active': true,
}{
"name": "FormatForge",
"active": true
}Frequently Asked Questions
What is a JSON Validator?
A JSON Validator checks if your JSON data complies with RFC 8259 syntax specifications. It displays detailed error messages pinpointing exactly where syntax issues exist, such as missing brackets, quotes, or trailing commas.
How does the validator work?
All syntax checks are executed directly in your browser using standard JavaScript parsing routines. Your JSON data is never uploaded or sent to any server.
What are common JSON validation errors?
Common errors include using single quotes instead of double quotes, trailing commas after the last item in an array or object, missing quotation marks around property keys, and unmatched brackets or braces.
Is there a file size limit?
Our validator runs client-side and can easily inspect files up to 5-10MB in real-time, depending on your browser and system performance.
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