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OpenAPI / Swagger Editor

OpenAPI / Swagger Editor

Parse, validate, and preview OpenAPI 3.x or Swagger 2.0 documents

Spec Input

2 spaces

About this tool

This tool parses an OpenAPI (3.x) or Swagger (2.0) document supplied as JSON or YAML, validates that it declares an API version and the required info/paths blocks, and renders a browsable preview: the API title and version, declared servers, every operation (method + path + summary), and a count of reusable schemas. The parsed document is re-emitted as formatted JSON. Use it to sanity-check a spec or explore an API without external tooling. Parsing is client-side; nothing is uploaded.

Examples & Use Cases

Minimal OpenAPI 3.1

openapi: 3.1.0
info:
  title: Pet Store API
  version: 1.0.0
paths:
  /pets:
    get:
      summary: List all pets
    post:
      summary: Create a pet

The smallest valid OpenAPI 3.x document — version, info, and a single path with two operations.

Legacy Swagger 2.0

swagger: "2.0"
info:
  title: Legacy API
  version: 0.9.0
host: api.example.com
basePath: /v1
paths:
  /users:
    get:
      summary: List users

Older Swagger 2.0 specs are detected and parsed the same way.

    Related guides

    OpenAPI 3.x vs Swagger 2.0: What Changed and How to Validate a Spec

    How the API-description format evolved from Swagger 2.0 to OpenAPI 3.x, the practical differences that break importers, and how to sanity-check a spec before shipping it.

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