# Testing the Swagger Petstore: Manually Testing An API Using Swagger UI

DevFeed: [Testing the Swagger Petstore: Manually Testing An API Using Swagger UI](<https://devfeed.tech/articles/testing-the-swagger-petstore-manually-testing-an-api-using-swagger-ui-22427.md>)

Original publisher: [Read original article](<https://www.tjmaher.com/2026/09/testing-swagger-petstore-manually.html>)

Author: T.J. Maher (noreply@blogger.com)

Published: 2026-09-07T16:43:41Z

Content type: tutorial

Language: en

Sources: [T.J. Maher](<https://devfeed.tech/sources/t-j-maher.md>)

Topics: [Swagger](<https://devfeed.tech/topics/swagger.md>), [Testing](<https://devfeed.tech/topics/testing.md>), [API](<https://devfeed.tech/topics/api.md>), [OpenAPI Specification](<https://devfeed.tech/topics/openapi.md>)

Tags: [api](<https://devfeed.tech/tags/api.md>), [auth](<https://devfeed.tech/tags/auth.md>), [authentication](<https://devfeed.tech/tags/authentication.md>), [authorization](<https://devfeed.tech/tags/authorization.md>), [http](<https://devfeed.tech/tags/http.md>), [openapi](<https://devfeed.tech/tags/openapi.md>), [payload](<https://devfeed.tech/tags/payload.md>), [schema](<https://devfeed.tech/tags/schema.md>), [swagger](<https://devfeed.tech/tags/swagger.md>), [testing](<https://devfeed.tech/tags/testing.md>), [ui](<https://devfeed.tech/tags/ui.md>)

## AI overview

A practical guide to manually testing the Swagger Petstore API through Swagger UI. It covers happy-path, negative, boundary and edge-case, authentication and authorization, and contract and schema validation tests using the browser-based "Try it out" feature.

## Source excerpt

With the last post, Testing the Swagger Petstore: Reviewing API Documentation Formatted in OpenAPI 3.0 with Swagger UI we started exploring an API with Swagger UI, such as the Swagger Petstore at https://petstore3.swagger.io/ Here, we will start exploring how to test an API using the Swagger UI. The tests we can run are: Happy Path Testing, checking the Positive Scenarios Negative Testing, reviewing the Invalid Inputs & Error Handling Boundary & Edge Case Testing, checking how the API handles the extreme limits of allowed input ranges Authentication & Authorization Testing Contract and schema validation We can see in the Swagger PetStore there are three tag groups: Pet, Store, and User. Because this is a Swagger UI doc, we can perform manual testing using only the "Try it out" feature in Swagger UI. No external tools needed! Live HTTP requests can be executed directly from your browser. Types of Testing for the API Here are a few types of testing and examples you can do in Swagger UI Happy path Functional Testing Pet POST /pet: add a new pet with a complete, valid payload. Verify 200 and that the response echoes the submitted fields. PUT /pet: update the pet you just created. Verify the change persists on a follow-up GET. GET /pet/{petId}: retrieve the pet by the ID returned from the POST. GET /pet/findByStatus: query with each valid status value (available, pending, sold) individually. GET /pet/findByTags: query with a tag that exists on a pet you created. POST /pet/{petId} (form data): update name/status via form fields instead of JSON body. POST /pet/{petId}/uploadImage: upload a valid image file, verify response message and metadata. DELETE /pet/{petId}: delete a pet you created, then confirm GET on that ID now fails. Store POST /store/order: place an order with valid petId, quantity, shipDate, status. GET /store/order/{orderId}: retrieve the order just placed. GET /store/inventory: verify it returns a status-to-count map without needing auth. DELETE /store/orde