Awesome API Clients

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

Web-Based

• 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
• gRPC UI - An interactive web UI for gRPC, along the lines of postman
• Yaade (repo) - Yaade is an open-source, self-hosted, collaborative API development environment
• Prestige (repo) - A text-based in-browser HTTP client, an interface-less Postman alternative
• Requestly (repo) - A Browser extension with API Client, API Mocking & API Interception and Modification capabilities.

Desktop

• Bruno (repo) - Opensource IDE For Exploring and Testing APIs
• Yaak (repo) - The most intuitive desktop API client
• API Dash - API Dash is a beautiful open-source cross-platform API Client
• ezy (repo) - GUI client for gRPC/gRPC-Web
• BloomRPC - (unmaintained) The missing GUI Client for gRPC services
• Milkman - An Extensible Request/Response Workbench
• Insomnium - (unmaintained) Insomnium is a 100% local and privacy-focus open-source API client (based on Insomnia)
• Pororoca (repo) - A HTTP inspection tool with support for HTTP/2 and HTTP/3, an alternative to Postman
• Nightingale REST Client (repo) - A modern, open-source, resource-efficient REST API client for Windows
• Requestly (repo) - A desktop app with API Client, API Mocking & API Interception and Modification capabilities.
• Cartero (repo) - A native, lightweight, multiplatform and free HTTP client
• Voiden (repo) - Local, file-based, keyboard-first API client using executable Markdown, designed for version-controlled workflows (no sign up required)
• EasyPostman - An open-source API debugging and performance testing tool inspired by Postman and a simplified JMeter

IDE

• VS Code REST Client (repo) - Send HTTP request and view the response in Visual Studio Code
• restclient.el - HTTP REST client tool for emacs
• verb - Organize and send HTTP requests from Emacs
• rest.nvim - A fast Neovim http client written in Lua
• kulala.nvim - A minimal REST-Client Interface for Neovim.
• resterm - Terminal REST/Graphql/gRPC client written in Go.

CLI

• 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
• posting - The modern API client that lives in your terminal
• 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
• httpYac (repo) - Yet another REST client to send REST, SOAP, GraphQL and gRPC requests
• ATAC (repo) - A simple postman like API client for terminal
• Better Curl Saul - Workspace-based HTTP client with interactive variable prompting and TOML configuration
• Slumber (repo) - A terminal-based HTTP/REST client, with TUI and CLI usage mods
• resto - Send pretty HTTP & API requests with TUI

Automated Testing

• 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
• abao - REST API automated testing tool based on RAML
• HttpRunner (repo)
• k6 (repo) - A modern load testing tool, using Go and JavaScript
• Artillery (repo) - Load testing at cloud-scale