API Clients

cURL is a computer software project providing a library and command-line tool for transferring data using various protocols with URL syntax: supporting FTP, FTPS, SCP, SFTP, HTTP, HTTPS, TFTP, TELNET, DICT, LDAP, LDAPS and FILE.

Lightweight open source API client for testing endpoints, saving requests as plain text files, offline use, git-compatible collaboration, and privacy-focused storage.

Collaborative platform for API development providing design, specifications, testing, documentation, and requests with free and paid subscription plans.

A powerful REST API Client with cookie management, environment variables, code generation, and authentication for Mac, Window, and Linux.

The API client for modern developers. Call REST, GraphQL, and gRPC APIs from a simple and intuitive app.

Hoppscotch is an open-source API development ecosystem. It helps you create your requests faster, saving you precious time on your development.

ApiArk is a local-first API client built with Tauri v2 and Rust. No login, no cloud, no telemetry. Supports REST, GraphQL, gRPC, WebSocket, SSE and MQTT from one interface. Collections are stored as plain YAML files on your filesystem, fully git-diffable.

Insomnium is a fast local API testing tool that is privacy-focused and 100% local. For testing GraphQL, REST, WebSockets and gRPC. This is a fork of Kong/insomnia.

Free, open source, git-native API client. A local-first, account-free Postman alternative with a built-in MCP server, SOAP/GraphQL, request chaining and performance runs.

HTTPie (pronounced aitch-tee-tee-pie) is a command line HTTP client. Its goal is to make CLI interaction with web services as human-friendly as possible. It provides a simple http command that allows for sending arbitrary HTTP requests using a simple and natural syntax, and...

RapidAPI for Mac (formerly Paw) is a full-featured HTTP client that lets you test and describe the APIs you build or consume. It has a beautiful native macOS interface to compose requests, inspect server responses, generate client code and export API definitions.

Voiden.md is an offline-first, Git-native API workspace that unifies specs, docs, tests, and mocks using programmable Markdown blocks. Build APIs the way you actually work.

Eviware, the maker of soapUI, Web Service Testing Leader

soapUI is a tool for functional testing, mainly of web services like SOAP based web services and RESTful web services, but also HTTP based services and JMS Services as well as databases. soapUI is an open source and compl.

API testing tool. Which allows web developers to create and test custom HTTP requests.

xh is a friendly and fast tool for sending HTTP requests. It reimplements as much as possible of HTTPie's excellent design, with a focus on improved performance.

Reqable is a modern cross-platform project, designed for API development, testing, and debugging. Reqable fully supports HTTP1 and HTTP2 and partially supports HTTP3(QUIC).

Practical and easy-to-use software tool for testing HTTP applications and services.

Hurl is a command line tool that runs HTTP requests defined in a simple plain text format. It can capture values, evaluate queries on headers and body response. It is very versatile: it can be used for both fetching data and testing HTTP sessions.

Native API testing tool, supporting HTTP and gRPC protocols, workspaces, environments, request management, various content types, and dark mode.

Design and debug APIs in a powerful visual editor. Describe and debug easily with JSON Schema support. Apidog is a complete set of tools that connects the entire API lifecycle, helping R&D teams implement best practices for API Design-first development.

The collaboration platform for building, documenting and testing APIs together.

ArdorQuery is a cross-platform tool for performing any HTTP(S) endpoints like REST API, HTML, Images, GraphQL, OData etc.

A free, open-source Postman-style API tester you run locally. Record browser requests, auto-generate chained tests, and ship them straight to your CI—no sign-ups, no cloud, just code.

Powerful HTTPie alternative in Go.

Zaku is a native Rust, local-first, open-source API client engineered for speed and productivity.