Validate OpenAPI 3.2, 3.1, 3.0 & Swagger 2.0 specifications. Paste JSON/YAML, upload files, or fetch from URL.
1Validating for a code generator?
Tool-specific guides to the schema errors that break client generation.
Tell us which generator or importer your spec has to satisfy — the most-requested target gets first-class support next.
Paste or upload your OpenAPI spec and click Validate to see a live preview.
Ensuring your API specification validates against the official standard is crucial for generating accurate documentation and SDKs.
Invalid JSON or YAML formatting
Adherence to OAS 3.0, 3.1 or 3.2
Required properties checks
OpenAPI 3.2
Latest release, fully supported
OpenAPI 3.1
Latest standard with webhooks
Swagger 2.0 & OAS 3.0
Full backward compatibility
OpenAPI Errors Cheat Sheet
The 8 most common validation errors with broken & fixed snippets.
Four simple steps to validate your OpenAPI specification.
Paste or Upload
Copy your OpenAPI JSON/YAML content or upload a file directly.
Instant Feedback
Our validator parses your spec against official schemas in real-time.
Fix & Retry
View detailed error messages to quickly resolve issues.
Preview & Publish
Once valid, preview your documentation and publish it instantly.