JSON Validator Online
Free online JSON validator. Check if your JSON is valid with detailed error messages showing exact line and column of syntax errors.
JSON Input
💡 What is this
JSON Validator
- A JSON validator checks whether a string is well-formed JSON.
- It catches missing commas, trailing commas, unquoted keys, and mismatched brackets — pinpointing exactly where problems occur.
📖 How to use
Step by Step
- Paste your JSON into the input area
- Click Validate or press Ctrl+Enter
- Green = valid with type info; Red = exact error location
- Fix errors and re-validate
🎯 Use cases
When to use
- Debugging API request/response bodies
- Validating hand-edited config files
- Checking JSON before database import
- Troubleshooting webhook payloads
Frequently Asked Questions
What makes JSON invalid?▾
Common issues include trailing commas, single quotes instead of double quotes, unquoted keys, missing colons or commas, and comments (JSON does not support comments).
Does this fix invalid JSON?▾
This tool identifies errors but does not auto-fix them. It shows you exactly where the problem is so you can correct it manually.