Awesome Postman alternatives and Awesome Insomnia alternatives (why?).

Criteria: open-source, more than 200 stars and 2 contributors.

If you wish to contribute: start a pull request

• Restfox (repo) - Offline-first web HTTP client
• Hoppscotch (repo) - Open source API development ecosystem
• Firecamp (repo) - Open Source Postman Alternative inspired by VS Code DX
• RecipeUI (repo) - RecipeUI is the Postman alternative with type safety built in
• gRPC UI - An interactive web UI for gRPC, along the lines of postman

• Bruno (repo) - Opensource IDE For Exploring and Testing APIs
• API Dash - API Dash is a beautiful open-source cross-platform API Client
• ezy (repo) - GUI client for gRPC/gRPC-Web
• Milkman - An Extensible Request/Response Workbench
• Insomnium - Insomnium is a 100% local and privacy-focus open-source API client (based on Insomnia)

• IntelliJ HTTP Client - Create, edit, and execute HTTP requests directly in the IntelliJ IDEA
• VS Code REST Client (repo) - Send HTTP request and view the response in Visual Studio Code
• RESTClient - A Firefox debugger for RESTful web services
• restclient.el - HTTP REST client tool for emacs
• verb - Organize and send HTTP requests from Emacs

• curl (repo) - Command line tool and library for transferring data with URLs (since 1998)
• HTTPie (repo) - HTTPie CLI: human-friendly HTTP client for the API era
• grpcurl - Like cURL, but for gRPC: Command-line tool for interacting with gRPC servers
• xh - Friendly and fast tool for sending HTTP requests
• curlie - The power of curl, the ease of use of httpie
• HttpRepl - Lightweight, cross-platform command-line tool that's supported everywhere .NET Core is supported
• ain - A HTTP API client for the terminal, uses curl, wget or httpie to make the actual calls
• evans - Evans: more expressive universal gRPC client

• Step CI (repo) - Open-source API Test Automation framework
• Hurl (repo) - Hurl, run and test HTTP requests with plain text.
• Karate (repo) - Test Automation Made Simple
• Tavern (repo) - Automated RESTful API testing
• Venom - Manage and run your integration tests with efficiency
• pyresttest - Python Rest Testing
• runn - runn is a package/tool for running operations following a scenario
• scenarigo - An end-to-end scenario testing tool for HTTP/gRPC server
• Schemathesis (repo) - Specification-centric API testing tool for Open API and GraphQL-based applications
• Dredd - Language-agnostic HTTP API Testing Tool
• HttpRunner (repo)
• k6 (repo) - A modern load testing tool, using Go and JavaScript
• Artillery (repo) - Load testing at cloud-scale