Fix JSON for Postman (API Testing)
Paste JSON that won't work in Postman. This tool repairs formatting for request bodies, validates structure, and ensures Postman compatibility.
Postman JSON Issues
Postman's Body → raw → JSON requires valid JSON. This tool fixes trailing commas, smart quotes from AI, and validates structure for API testing.
Why Fix JSON for Postman?
Postman API testing requires valid JSON in request bodies, test scripts, and environment variables. Syntax errors (trailing commas, smart quotes, unescaped characters) cause "Error: Unexpected token" failures, blocking API testing. Auto-fixing prepares JSON for Postman—enabling smooth testing workflows.
Common Use Cases
- API request bodies: Fix JSON before pasting into Postman POST/PUT request body
- Test assertions: Validate JSON in Postman test scripts (pm.expect)
- Environment variables: Format JSON stored in Postman environment/global variables
- Mock servers: Prepare JSON examples for Postman mock server responses
- Documentation: Clean JSON for Postman collection documentation
- Pre-request scripts: Fix JSON manipulated in Postman pre-request scripts
Why This Tool?
- Postman-ready: Formats JSON to meet Postman parser requirements
- Error prevention: Catches syntax issues before they break requests
- Instant fixing: Clean and validate JSON in milliseconds
- 100% client-side: Your API test data never touches our servers
- Free forever: Unlimited JSON fixing for Postman testing
Pro tip: After fixing, paste into Postman and use "Beautify" for formatting. For JWT testing, use our JWT Decoder.