Format Swagger & OpenAPI JSON
OpenAPI specs can be thousands of lines long. Our formatter makes them readable with proper indentation and syntax highlighting. Validate your API spec before importing into Swagger UI or Postman.
Open JSON Formatter Free →Features
- Format OpenAPI 3.0 and Swagger 2.0
- Validate spec structure
- Proper nested indentation
- Prepare for Swagger UI import
- Works with Postman exports
- Handles large specification files
How It Works
1
Open the Tool
Go to JSON Formatter
2
Use for Free
No signup, works in your browser
3
Download Result
Get your output instantly
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