The top-rated alternative to Postman is Insomnia REST Client, which is open source with a free version. People also recommend Hoppscotch, HTTPie for Terminal, Bruno and soapUI. You're spoiled for choice with API Clients like Postman: we list more than 100 alternatives for Windows, Mac, Linux, the web and self-hosting.
Used httpyac CLI tool underneath, which helps you execute _.http and _.rest files. This can be used to quickly execute a single *.http file, but also to execute all files in a folder. httpyac supports HTTP, Rest, GraphQL, WebSocket und gRPC...
Milkman is a JavaFx-based workbench for crafting requests / responses. It is not limited to e.g. http (or more specifically rest) requests but can be extended in any imaginable way. It is optimized for fast startup and efficient workflow.
United States
apiman is an open source API management layer that streamlines repetitive tasks often required when providing an API, such as implementing security, throttling and billing.
API Tester is the first mobile app to test any type of API on the go. Test REST, GraphQL, WebSocket, SOAP, JSON RPC, XML, HTTP, and HTTPS APIs completely for free, on iOS or Android.
Humlix shows you an easy way of generating tests for your web APIs. All you need to do is create a test request using the test request builder within Humlix and give an example of how your endpoints look and what type of data they want.
API integration platform for testing, prototyping, and running of any API flow. The right tool for successful API flow integration - nice, easy, simple, and cheap.
United Kingdom
API Test Base is a free, offline-first tool for testing APIs and their side effects — the records an API writes to a database, the messages it publishes to a queue, the downstream services it calls. Test cases are created with a no-code / low-code UI, and the same tests can be...
RestCase is a security-focused API development platform that enables its users to rapidly create secure microservices, mock them in order to start testing, monitor APIs and collaborate on their development and testing.
APITree is a free cloud-based API tool to create, manage and share OpenAPI specifications. It converts your OpenApi v2 / v3 specification into a beautiful technical API documentation. Public API documentation is hosted for free.
EchoAPI is an all-in-one API development collaboration platform that offers essential features like API debugging, design, automated testing, stress testing, and documentation generation.
RESTClient can be used to test variety of HTTP communications and RESTful webservices. Friendly GUI, rich functionalities.
India
