Dev tools · alternatives · 2026
24 alternatives to Generate API tests for OpenAPI endpoints
CATS is a REST API Fuzzer and negative testing tool for OpenAPI endpoints. CATS automatically generates, runs and reports tests with minimum configuration and no coding effort. Tests are self-healing and do not require maintenance. - Endava/cats
Below are 24 products that do a similar job, ranked by how close each is in meaning and then by launch-day votes. Prices are shown for the 1 we have checked on their own sites, 1 of them free or with a free tier. Generate API tests for OpenAPI endpoints launched in 2020; newer entries below may have overtaken it.
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Generate, edit, lint & test your API workflow in one place
2025 · app.getelva.ai · its alternatives →
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Develop APIs fast + automatically detect endpoints
2025 · fastrequest.apidog.com · its alternatives →
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Effortlessly discover API behaviour with a Chrome extension that automatically generates OpenAPI specifications in real time for any app or website.
2023 · github.com · its alternatives →
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I’ve been working on an open-source CLI tool called Dochia for a while now. The reason for building it: in microservices architectures, testing is repetitive: every service exposes APIs, and much of the testing process will share a similar set of test cases: negative inputs, boundary cases, encoding quirks, invisible characters. I wanted a tool that could automate this shared layer of testing instead of doing it manually across dozens of services. So what Dochia does: reads your OpenAPI spec; generates thousands of smart, edge-case payloads automatically and produces detailed reports with…
2025 · github.com · its alternatives →
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Hey HN! We've developed OpenAPI AutoSpec, a tool for automatically generating OpenAPI specifications from localhost network traffic. It’s designed to simplify the creation of API documentation by just using your website or service, especially useful when you're pressed for time. Documenting endpoints one by one sucks. This project originated from us needing it at our past jobs when building 3rd-party integrations. It acts as a local server proxy that listens to your application’s HTTP traffic and automatically translates this into OpenAPI 3.0 specs, documenting endpoints, requests, and…
2024 · github.com · its alternatives →
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Elvafree tier, from $100/mo▲303Goodbye, Postman. Your APIs have new consumers
Sep 2026 · getelva.ai · its alternatives →
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Generate custom data & API to build apps in less than 30s
2021 · retool.com · its alternatives →
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Hi, this is Mish and Sebastian. We are working on Step CI - a fully automated API testing platform for developers. Step CI works programming-language independent and for different API paradigms (REST, GraphQL, XML). Our CLI and test runner are available on GitHub (https://github.com/stepci) under the MPLv2 license. Since our last launch, Step CI is now able to generate automated tests for your API based on your OpenAPI (Swagger) spec. This saves you a lot of time as you never have to write and maintain your tests again! We would like to invite you to try our tool and give us…
2022 · stepci.com · its alternatives →
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Black-box fuzzer that fuzzes APIs based on OpenAPI specification. Find bugs for free! - matusf/openapi-fuzzer
2021 · github.com · its alternatives →
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Computer generated cats - refresh to get a new one
2019 · its alternatives →
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Progressive Web App for generating mocked data from an OpenAPI specification - Fredx87/openapi-mock-generator
2020 · github.com · its alternatives →
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PS: Assuming a REST architecture.
2014 · github.com · its alternatives →
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Port OpenAPI Specs to Postman Collections, inject test suite and run via Newman 👨🏽🚀 - apideck-libraries/portman
2021 · github.com · its alternatives →
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Generate images with the corresponding HTTP status code
2015 · http.cat · its alternatives →
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Fern▲260We built the world’s first generated, idiomatic gRPC and REST SDK. If you have public gRPC and REST endpoints, Fern is the SDK provider for you.
2025 · buildwithfern.com · its alternatives →
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Hey HN, We just shipped a new AI-powered feature... BUT the "AI" piece is largely in the background. Instead of relying on a chatbot, we've integrated AI (with strict input & output guardrails) into a workflow to handle two specific tasks that would be difficult for traditional programming: 1. Identifying the most relevant base URL from HAR files, since it would be tedious to cover every edge case or scenario to omit analytics, tracking, and other network noise. 2. Generating synthetic data for API requests by passing the API context and faker-js functions to GPT-4. The steps are broken down…
2024 · docs.multiple.dev · its alternatives →
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Generate and share OpenAPI specs with AI
2025 · api.dev · its alternatives →
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OpenAPI linting, diffing and testing. Optic helps prevent breaking changes, publish accurate documentation and improve the design of your APIs. - optic/docs/generate-openapi.md at main · opticdev/optic
2023 · github.com · its alternatives →
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Octrafic▲130Test your APIs in plain English, straight from the terminal
Mar 2026 · its alternatives →
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Ranked by how close each launch is in meaning, then by votes. Prices were read from each product’s own site when checked and can change. Refine with your own description →