Validate OpenAPI documents the way an editor should

Paste or open a spec and OASForge lints it continuously — like Swagger Editor, but with messages that explain why something is wrong for your spec version, and with one-click fixes for the common mistakes.

What the validator catches

• Misplaced and unknown properties, with hints when a key belongs to a different OpenAPI version (a Swagger 2.0 key used in 3.x, a 3.1-only keyword in 3.0, and so on)
• Wrong value types — the classic version: 1.0 that should be a quoted string
• Security requirements that reference schemes which don’t exist in components.securitySchemes
• Unresolved $refs, invalid status codes, example/examples conflicts, duplicate server URLs, ignored fixed headers in parameter lists
• Version-specific schema rules: nullable in 3.1+, JSON Schema 2020-12 keywords in 3.0, exclusiveMinimum/Maximum shape differences between versions

Issues you can act on

Every issue is clickable and jumps to the offending line. Most carry a Fix button: quote the value, create the missing security scheme, remove the offending property, add the missing description or responses block. Warnings can be dismissed — and restored — so noisy-but-known issues don’t bury real ones.

Versions covered

Swagger 2.0, OpenAPI 3.0.x, 3.1.x and 3.2.x are all recognized, each validated against its own allowed keys. Documents with a newer minor version than the editor knows are handled permissively with an informational note instead of a wall of false errors.