| 1 |  BrunoOpensource IDE For Exploring and Testing API's (lightweight alternative to Postman/Insomnia) | 4.3.0 | Open source | October 22, 2026 | — | 120.8K ↓ |
| 2 |  InsomniaThe Desktop API client for REST and GraphQL. Make requests, inspect responses. | 13.3.1 | Open source | October 9, 2026 | — | 153K ↓ |
| 3 |  YaakThe most intuitive desktop API client. Organize and execute REST, GraphQL, WebSockets, Server Sent Events, and gRPC. | 2026.9.0 | Open source | October 10, 2026 | — | 19.2K ↓ |
| 4 |  RenderDocA stand-alone graphics debugging tool | 1.46.0 | Open source | August 31, 2026 | 88.4 MB | 4.9K ↓ |
| 5 |  Altair GraphQL ClientA beautiful feature-rich GraphQL Client for all platforms. | 8.5.11 | Open source | October 10, 2026 | — | 20.1K ↓ |
| 6 |  HTTPieHTTPie for Web & Desktop — cross-platform API testing client for humans. Painlessly test REST, GraphQL, and HTTP APIs. | 2025.2.0 | Free | March 14, 2025 | — | 65.8K ↓ |
| 7 |  ResponsivelyAppA modified browser built using Electron that helps in responsive web development. | 1.18.0 | Open source | February 16, 2026 | — | 7.4K ↓ |
| 8 |  HurlHurl is a command line tool that runs HTTP requests defined in a simple plain text format. | 8.0.1 | Open source | April 29, 2026 | — | 6.2K ↓ |
| 9 |  SoapUIAn advanced API testing utility. | 5.10.0 | Open source | June 2, 2026 | 195.8 MB | 659.2K ↓ |
| 10 |  JACK2JACK2 aka jackdmp is a C++ version of the JACK low-latency audio server for multi-processor machines. It is a new implementation of the JACK server core features that aims at removing some limitations of the JACK1 design. | 1.9.22 | Open source | December 5, 2024 | — | 35K ↓ |
| 11 |  Dr. MemoryMemory monitoring tool capable of identifying memory-related programming errors. | 2.6.20434 | Open source | March 28, 2026 | — | 18.8K ↓ |
| 12 |  xhFriendly and fast tool for sending HTTP requests | 0.26.3 | Open source | October 21, 2026 | — | 4.2K ↓ |
| 13 |  ARMClientA simple command line tool to invoke the Azure Resource Manager API | 1.9 | Open source | July 16, 2025 | — | 102.1K ↓ |
| 14 |  West Wind WebSurgeWebSurge - An Http REST Client and Load Testing Tool for Windows | 3.0.4.0 | Proprietary | May 15, 2026 | — | 34.4K ↓ |
| 15 | Iinsomnia-designerCollaborative API Design Tool for designing and managing OpenAPI specs | 2020.5.2 | Open source | | — | 1K ↓ |
| 16 |  HTTP ToolkitHTTP Toolkit is a beautiful & open-source tool for debugging, testing and building with HTTP(S) on Windows, Linux & Mac. | 1.27.3 | Open source | October 21, 2026 | — | 4.1K ↓ |
| 17 |  RizinUNIX-like reverse engineering framework and command-line toolset. | 0.9.1 | Open source | August 19, 2026 | — | 1.7K ↓ |
| 18 |  HoppscotchOpen Source API Development Ecosystem | 26.9.0-0 | Open source | September 30, 2026 | — | 1.5K ↓ |
| 19 | Ccheat-engineTool for modifying/debugging single player games and applications. | 7.6 | Free | | — | 69.3K ↓ |
| 20 |  HttpMasterHttpMaster is a professional testing tool for HTTP applications, with special focus on RESTful web services and web API applications. | 7.1.2 | Proprietary | October 8, 2026 | — | 10.5K ↓ |
| 21 |  Postman CLIThe Postman CLI is a secure command-line companion for Postman | 1.16.0 | Proprietary | June 10, 2025 | — | 17.1K ↓ |
| 22 |  WhoCrashed Home EditionComprehensible crash dump analysis, find out why your system crashed. | 7.10 | Free | June 6, 2025 | 11.4 MB | 38.4K ↓ |
| 23 | MmockoonEasiest and quickest way to run mock APIs locally. | 9.9.0 | Open source | | — | 37.4K ↓ |
| 24 |  HttpMaster Express EditionHttpMaster Express is a professional testing tool for HTTP applications, with special focus on RESTful web services and web API applications. | 5.9.3 | Proprietary | January 6, 2025 | — | 7.5K ↓ |
| 25 |  Hoppscotch AgentThe Hoppscotch Agent is a micro application designed to mitigate the challenges posed by CORS in modern web browsers. | 0.1.18 | Open source | July 16, 2026 | — | ★ 80.7K |
| 26 |  VoidenThe offline, Git-native API workspace. | 2.2.2 | Open source | July 25, 2026 | — | 52 ↓ |
| 27 |  Inso CLISpeed up API CI/CD pipeline development | 2023.5.8 | Open source | September 8, 2023 | — | ★ 40.1K |
| 28 |  ProxymanDebug Network Faster & Smarter with Proxyman | 26.0.0 | Proprietary | October 14, 2026 | 194.2 MB | 3.4K ↓ |
| 29 | Kkeepass-plugin-keepasshttpA plugin for KeePass 2.x and provides a secure means of exposing KeePass entries via HTTP for clients to consume | 1.8.4.2 | Open source | | — | 12.3K ↓ |
| 30 | VVelocityVelocity gives your Windows desktop offline access to over 150 API documentation sets | 1.2.1.20436 | Proprietary | June 3, 2021 | — | 10.8K ↓ |
| 31 |  ScalarAn offline first API Client built for OpenAPI. | 1.1.35 | Open source | September 29, 2026 | 155.2 MB | ★ 16.3K |
| 32 |  ReqableAdvanced API Debugging Proxy. | 3.3.5 | Proprietary | October 23, 2026 | — | ★ 6.9K |
| 33 |  BowireInteractive multi-protocol API browser and CLI for .NET — gRPC, REST, GraphQL, SignalR, MCP, SSE, WebSocket, MQTT, Socket.IO, OData, Surgewave, Kafka, DIS, UDP. | 2.9.0 | Open source | September 30, 2026 | — | 486 ↓ |
| 34 |  TASKING winIDEAwinIDEA in conjunction with a Hardware debugger or a virtual ECU simulator is an IDE for debugging, testing, and analyzing embedded systems. | 9.21.417.4 | Proprietary | August 7, 2026 | — | 1.5K ↓ |
| 35 | BbombardierFast cross-platform HTTP benchmarking tool written in Go | 2.0.2 | Open source | | — | 1.5K ↓ |
| 36 |  Dev Proxy BetaDev Proxy Beta is a preview build of the command line tool for simulating APIs for testing apps | 4.0.0-beta.11 | Open source | October 21, 2026 | — | ★ 838 |
| 37 |  RequestlyIntercept & Modify HTTP Requests | 26.6.29 | Open source | September 21, 2026 | — | 14 ↓ |
| 38 |  simple-http-serverSimple HTTP(s) Server | 0.8.0 | Open source | March 17, 2026 | — | ★ 3.5K |
| 39 |  RestfoxRestfox | 0.40.0 | Open source | August 12, 2025 | — | ★ 2.8K |
| 40 |  Nitro CLIA performant, feature-rich GraphQL IDE / API Cockpit that helps developers and data scientists to explore, share, and test any GraphQL API. | 16.0.0-p.10.22 | Open source | December 28, 2025 | — | ★ 5.8K |
| 41 |  Dev ProxyDev Proxy is a command line tool for simulating APIs for testing apps | 3.3.1 | Open source | September 22, 2026 | — | ★ 838 |
| 42 |  OpenDirectoryDownloaderIndexes open directories listings in 130+ supported formats, including FTP(S), Google Drive, Bhadoo, GoIndex, Go2Index (alternatives), Dropbox, Mediafire, GoFile, GitHub. | 5.0.0.0 | Open source | October 20, 2026 | — | ★ 1.4K |
| 43 |  RayRay is a desktop app that vastly improves your debugging experience. It is a dedicated window to send debugging information to. | 2.5.1 | Open source | June 11, 2023 | — | ★ 625 |
| 44 |  Titanium InspectorDesktop HTTP(S) traffic debugger for Titanium Web Proxy. | 7.0.21 | Proprietary | October 10, 2026 | — | ★ 2K |
| 45 |  OpenAPI.NET HidiContains a useful object model for OpenAPI documents in .NET along with common serialisers to extract raw OpenAPI JSON and YAML documents from the model. | 3.10.2.0 | Open source | September 22, 2026 | — | ★ 1.6K |
| 46 |  ProxelarScriptable local traffic workbench for HTTP, HTTPS, and WebSocket debugging | 0.6.1 | Open source | September 23, 2026 | — | ★ 1.1K |
| 47 |  armorUncomplicated, modern HTTP server | 0.4.14 | Open source | May 21, 2023 | — | ★ 1.7K |
| 48 |  FluxzyMITM HTTP debugging proxy for intercepting and altering HTTP/1.1, H2, and WebSocket traffic | 1.39.48.18975 | Open source | September 9, 2026 | — | ★ 372 |
| 49 | DdevdA small, self-contained, command-line-only HTTP server for developers | 0.9 | Open source | | — | 292 ↓ |
| 50 |  CarteroCartero is a graphical HTTP client that can be used as a developer tool to test web APIs and perform all kind of HTTP requests to web servers. | 26.0 | Open source | | — | ★ 1.1K |