Free toolOpenAPI 3.0 / 3.1

Validate and troubleshoot your OpenAPI spec

Paste, upload, or fetch your spec. Get instant feedback with actionable suggestions.

Formats
OpenAPI 3.0OpenAPI 3.1YAMLJSON
Highlights
  • Real‑time format detection
  • Actionable error hints
  • Dark mode ready
Tips

Use a small spec first to verify structure, then validate the full document.

OpenAPI specification

JSON
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