Free Online JSON Validator
JSON (JavaScript Object Notation) is the most popular data format for API payloads, config files, and web services. A single missing quote or comma can break an entire application.
Our free online JSON Validator checks your code against standard JSON syntax specifications in real time. Quickly locate syntax errors, misplaced braces, or improper string escaping before pushing data to production servers.
Key Features of Our Online JSON Validator
Instant Syntax Checking
Parses JSON payload instantly and catches syntax issues like missing commas or unquoted keys.
Detailed Error Output
Displays the precise error message to help you debug structural bugs quickly.
File & URL Import
Upload local `.json` files or fetch external API payloads directly via public URL.
100% Client-Side Execution
Your sensitive JSON payloads are parsed inside your browser without external server logging.
How to Use the JSON Validator
- Paste your raw JSON code into the Input panel or load it from a file/URL.
- Click "Validate JSON" to execute the syntax parser.
- Check the Validation Result panel for a success status or error report.
Frequently Asked Questions (FAQs)
Does this validator support single quotes in JSON?
No. According to standard JSON specifications (RFC 8259), string keys and string values must use double quotes.
Is my JSON uploaded to any server?
No. Validation runs entirely inside your browser using native JavaScript JSON engine.