So nutzt du: OpenAPI / Swagger Validator
- Paste your
openapi.yaml/swagger.jsonor open the file. - The version (OpenAPI 3.1, 3.0 or Swagger 2.0) is detected automatically.
- Fix schema errors first — each shows its location in the document.
- Review the additional checks and the endpoint list.
What gets checked
| Check | Details |
|---|---|
| Official schema | The document is validated against the OpenAPI Initiative’s JSON Schema for its version (3.1, 3.0 or Swagger 2.0): required fields, allowed keys, value types |
Broken $ref | Every local reference (#/components/schemas/Pet) must point to something that exists |
Unique operationId | Duplicates break SDK generators and documentation links |
| Path parameters | Every {param} in a path must be declared with in: path and required: true, and vice versa |
| Responses | Each operation needs at least one response |
| Hints | Missing operationId, servers or info.description |
OpenAPI versions
- Swagger 2.0 —
swagger: "2.0",definitions,host/basePath. - OpenAPI 3.0 —
components,servers,requestBody; schemas are a JSON Schema draft-04 subset withnullable. - OpenAPI 3.1 — fully aligned with JSON Schema 2020-12 (
type: [string, "null"]instead ofnullable), addswebhooks.
Limits
External references to other files or URLs are not fetched — bundle multi-file specs first (for example with redocly bundle). Schema validation reports structural problems; style rules such as naming conventions need a linter like Spectral. Validate example payloads against your schemas with the JSON Schema validator, check YAML syntax with the YAML validator, and try the live API with the API tester.
Auch gesucht als: swagger validator, openapi validator, validate openapi, openapi 3.1 validator, swagger 2.0 validator, openapi lint, api spec validator.
Passende Tools zu: OpenAPI / Swagger Validator
- JSON Formatierer — Füge JSON ein, um es zu formatieren, zu minifizieren oder zu prüfen.
- cURL to Code — Paste a curl command — from API docs or “Copy as cURL” in your browser’s DevTools — and get ready-to-run code for six languages, with headers, body and authentication carried over.
- JSONPath Tester — Type a JSONPath query and instantly see what it selects — with the exact path of each match.
- JSON to YAML — Paste JSON and get clean YAML for Kubernetes manifests, Docker Compose, GitHub Actions or any config file.
Häufige Fragen
Does it support OpenAPI 3.1?
Yes — OpenAPI 3.1.x, 3.0.x and Swagger 2.0 are each validated against their official schema.
Why are there so many errors for one mistake?
The official schemas use alternatives (oneOf), so one wrong value can fail several branches. The tool filters these down to the most specific messages; fix the first one and re-check.
Can it follow $refs to other files?
No, only references within the same document. Bundle multi-file specs into one file first.
Is my API spec uploaded?
No. Validation runs entirely in your browser, so internal API designs stay private.
Kann ich OpenAPI / Swagger Validator als Web-App installieren und offline nutzen?
Ja. OpenAPI / Swagger Validator ist eine installierbare Web-App (PWA) – sie wird über Ihren Browser installiert und nicht aus einem App-Store heruntergeladen. Klicken Sie oben auf dieser Seite in Chrome oder Edge (Windows, macOS, Linux, ChromeOS) auf „App installieren“ oder verwenden Sie auf Android-Geräten „Teilen“ → „Zum Startbildschirm hinzufügen“ auf dem iPhone und iPad bzw. „Datei“ → „Zum Dock hinzufügen“ in Safari 17+ auf einem Mac. Die App öffnet sich dann in einem eigenen Fenster mit einem eigenen Symbol, und da sie vollständig in Ihrem Browser ausgeführt wird, funktioniert sie auch offline. Firefox auf dem Desktop kann keine Web-Apps installieren. So funktioniert die Installation.