OpenAPI Toolkit
View, validate, diff, and put an OpenAPI/Swagger document to work — five tools covering the full spec lifecycle. All run entirely in your browser.
How these fit together
OpenAPI Viewer turns a raw OpenAPI/Swagger document into a readable, searchable list of endpoints — the fastest way to actually understand an API someone handed you. OpenAPI Validator checks the document itself for broken $refs, duplicate operation IDs, and other spec violations. OpenAPI Diff compares two versions and flags which changes are breaking versus safe — essential before shipping a v2. Once the spec is solid, put it to work: OpenAPI to Postman exports a ready-to-use collection, and OpenAPI Mock Generator generates realistic mock responses a frontend can build against before the real API exists.
OpenAPI Viewer
Browse an OpenAPI/Swagger document as a readable, searchable list of endpoints.
OpenAPI Validator
Check an OpenAPI/Swagger document for broken refs, duplicate IDs and other spec violations.
OpenAPI Diff
Compare two OpenAPI/Swagger versions and flag breaking vs. non-breaking changes.
OpenAPI to Postman
Convert an OpenAPI/Swagger document into a downloadable Postman collection.
OpenAPI Mock Generator
Generate realistic mock responses from an OpenAPI/Swagger document, exportable as MSW handlers.