Validate OpenAPI 3.x and Swagger 2.0 specifications instantly. Get detailed validation feedback, browse API endpoints by tag, and inspect schema details. All processing happens locally in your browser.
Tool History is a Supporter feature.
Tool Notes is a Supporter feature.
Paste your OpenAPI or Swagger specification in JSON or YAML format into the editor, or load one of the included sample specs to get started quickly.
Click Validate to check your spec for errors and warnings. The validator checks for required fields, invalid references, schema violations, and more.
See a list of all errors and warnings with line numbers and descriptions. Errors prevent the spec from being valid while warnings indicate best practice issues.
Switch to the Endpoints tab to see all API paths organized by tag. Each endpoint shows the HTTP method, path, summary, and available parameters.
Navigate to the Schemas tab to browse all defined data models. View property names, types, required fields, and descriptions for each schema.
The tool parses your specification as either JSON or YAML. It builds an internal representation of all paths, operations, schemas, and components defined in the spec.
Validation checks include required fields (info, paths, openapi version), valid HTTP methods, proper $ref resolution, schema type correctness, and adherence to the OpenAPI or Swagger specification format.
All paths and HTTP methods are extracted and grouped by their tags. Operations without tags are grouped under a default category. Parameters, request bodies, and response codes are displayed for each operation.
Component schemas (OpenAPI 3.x) and definitions (Swagger 2.0) are extracted and displayed as browsable trees. You can inspect each property's type, format, description, and whether it is required.
The validator supports OpenAPI 3.0.x and 3.1.x as well as Swagger 2.0. These cover the vast majority of API specifications in use today. OpenAPI 3.1 is the latest version and aligns with JSON Schema 2020-12.
