OpenAPI Validator
Basic structural check for OpenAPI/Swagger specs — required top-level fields, non-empty paths, and $ref presence. A heuristic screen, not a full spec validation: passing here does not guarantee a valid spec. Code never leaves your device — formatting and validation run locally in your browser.
How to Use the OpenAPI Validator
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Frequently Asked Questions
Which OpenAPI versions?
The check looks for 2.0/3.x markers and top-level structure only — it never parses YAML or resolves $refs, so nested chains and Schema Objects are not actually verified. For full validation, use a dedicated spec validator.
What breaks most?
Missing required fields, wrong types, and unresolvable $refs.
Errors listed how?
Each violation with its JSON path for direct fixing in your editor.
Is my OpenAPI spec uploaded anywhere?
No — validation runs locally in your browser, free with no signup.
Which version and layout does it expect?
Only 3.x is checked (a 2.0 marker is flagged); paths must look like /name: lines, methods need at least 2-space indent (get/post/put/…), responses blocks need 4-space indent, and each response needs a description — mis-indented YAML is the most common failure.
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Last updated October 2026