The best tools and resources for Api Testing
Over 43+ awesome tools and resources on the internet to supercharge your Api Testing.
Portman
FreePort OpenAPI Specs to Postman Collections, inject test suite and run via Newman
cypress-ajv-schema-validator
FreeStreamlining JSON Schema Validation in Cypress

API Tester
FreeMobile app for iOS and Android for testing and using APIs.

SuperTest
FreeSimplifying HTTP Assertions for Node.js
PlayPI
FreeYour Local API Testing Playground.

Fake API
FreeFree public API to test API endpoints and retrieve dummy JSON data swiftly.

OpenAPI AutoSpec
FreeAutomatically generates OpenAPI specifications in real-time.

Keploy
FreeGenerate tests and stubs for your application that actually work!

Firecamp
Free PlanDesign, develop, test, and document their APIs effortlessly.

gaxios
FreeAn HTTP request client that provides an Axios-like interface over top of node-fetch.

Bruno
FreeOpensource IDE For Exploring and Testing Api's (lightweight alternative to postman/insomnia)

Mokku
FreeMock API calls seamlessly

OpenAPI DevTools
FreeChrome extension that generates API specs for any app or website
PactumJS
FreeA REST API testing tool to automate e2e, integration, contract,Β and component (or service-level) tests.
Fetchbook
FreeCLI tool to run and test your HTTP requests. Git friendly, 100% local.
RecipeUI
FreeOpen source Postman alternative with type safety built in.

Insomnium
FreePrivacy-focused and 100% local API testing tool.
Postman Contract Test Generator
FreeDynamic Test Generation with Open API Spec 3.0 and Postman

GraphQL Network Inspector
FreeA better network inspector for viewing and debugging GraphQL requests in Chrome and Firefox.

Thunder Client- VS Code
FreeThunder Client is a lightweight Rest API Client Extension for Visual Studio Code

snapstub
FreeSnapshot-based stub/mocking of APIs.
ezy
FreeGUI client for gRPC/gRPC-Web
ProAutoma API Tester
Free with Paid PlanOnline REST API client

Mockoon
Free with Paid PlanCreate mock APIs in seconds

Mock Service Worker
FreeMock API by intercepting requests on the network level. Seamlessly reuse the same mock definition for testing, development, and debugging.
Mocks Server
FreeNode.js mock server running live, interactive mocks in place of real APIs

Dummy
FreeRun mock server based off an API contract with one command
Json Model Validator
FreeA flexible, lightweight JSON Data validator and formatter

OC Mock
Freemock object testing framework that can be used to create stubs in iOS apps.

Advanced REST Client
FreeA better API testing tool
vcrpy
FreeAutomatically mock your HTTP interactions to simplify and speed up testing

ReqBin
FreeReqBin is an online API testing tool for REST and SOAP APIs.
httpbin.org
FreeHTTP Request & Response Service, written in Python + Flask.
Moq
FreeThe most popular and friendly mocking framework for .NET

URL Fetch
FreeCode Generator for HTTP Requests

Learn REST: A RESTful Tutorial
FreeLearn everything there is to know about REST apis with the this opensource resource.

Ajv JSON schema validator
FreeSecurity and reliability for JavaScript applications
Prestige
FreeA text-based HTTP client in the browser, an interface-less Postman.

Health Check Api
FreeAn easy way to execute a health check against your API endpoint.

Mountebank
FreeOver the wire test doubles
mitmproxy
FreeItβs a free and open source interactive HTTPS proxy
Curl
Freecommand line tool and library for transferring data with URLs

Postman
Free versionAPI Testing Tool