Free Alternative to Postman

Bruno represents a paradigm shift in API testing—your collections are stored as plain-text files using the Bru markup language, living alongside your code in Git repositories. No cloud accounts, no sync services, no vendor lock-in. Bruno's growth has been remarkable, expanding from 250,000 to over 600,000 monthly active users throughout 2025, with version 3.0 releasing in January 2026 adding workspaces, YAML support, and an integrated terminal.

The file-based approach makes API collections reviewable in pull requests, versionable with your codebase, and even readable by AI coding assistants. For teams tired of Postman's cloud sync and per-seat pricing, Bruno offers complete freedom—your API definitions become part of your infrastructure-as-code philosophy.

Hoppscotch (formerly Postwoman) is a blazing-fast, open-source API development ecosystem that works in your browser or as a desktop app. With over 57,000 GitHub stars and counting, it supports REST, GraphQL, WebSocket, MQTT, SSE, and Socket.IO protocols. The self-hosted option is particularly valuable—teams can deploy Hoppscotch on their own infrastructure, keeping all collections and test data within their security perimeter.

This makes it perfect for organizations with strict compliance requirements (HIPAA, SOC2, GDPR) or those who simply want complete control over their API testing data. The browser-based version requires zero installation, making it ideal for quick API debugging or exploratory testing.

Insomnia by Kong is a mature, open-source API client supporting REST, GraphQL, WebSockets, SSE, and gRPC. It strikes a careful balance between Postman's comprehensive feature set and Bruno's minimalist simplicity. The free version is genuinely useful—Local Vault provides 100% local storage with zero cloud dependency, and Scratch Pad mode works without any account whatsoever.

The plugin ecosystem includes over 100 community-built extensions for JWT generation, AWS SigV4 signing, mock data generation, and more. While Kong's 2019 acquisition initially raised community concerns about commercialization, the open-source core remains actively maintained with regular updates, and the free tier continues to serve solo developers exceptionally well.

RapidAPI for Mac (formerly Paw) is a premium native macOS API client known for its exceptionally polished interface and powerful features—now completely free for personal and professional use following RapidAPI's acquisition. It delivers a distinctly Mac-native experience with native animations, keyboard shortcuts, and system integration that cross-platform Electron apps simply cannot match. The tight integration with RapidAPI Hub lets you discover and test thousands of third-party APIs directly from the interface. Generate comprehensive API documentation in Swagger, RAML, and API Blueprint formats, and leverage dynamic values for complex authentication flows including OAuth 2.0 with PKCE.

HTTPie started as a beloved command-line HTTP client with intuitive syntax and colorful output, revolutionizing terminal-based API testing as a modern, human-friendly replacement for curl. The desktop app brings that same minimalist philosophy to a visual interface—simple, fast, and focused on the essentials without feature bloat. It's ideal for developers who live in the terminal but occasionally want a GUI for complex requests, multipart uploads, or exploring unfamiliar APIs. The offline-first architecture means your data stays on your machine, and the clean interface keeps you focused on the API rather than navigating through layers of menus and settings.

Thunder Client is widely considered the best Postman alternative for VS Code users, providing a seamless, integrated experience that allows developers to test APIs without ever leaving their code editor. This lightweight extension has surged in popularity precisely because it eliminates context switching—you can write code, test endpoints, debug responses, and commit changes all within Visual Studio Code. Collections are stored as JSON files that can be committed to your repository, enabling team sharing through Git. For developers who spend their entire day in VS Code, Thunder Client feels like a natural extension of their workflow rather than a separate application to manage.

Yaak was created by Gregory Schier, the original founder of Insomnia, who set out to build a simpler, faster, and more focused API testing tool after stepping away from his previous project. Yaak embodies a back-to-basics philosophy—fast, secure, and completely offline with local-only data storage, encrypted secrets, and zero telemetry or analytics tracking. It supports multiple protocols including REST, HTTP, GraphQL, gRPC, WebSocket, and Server-Sent Events. One particularly clever feature: you can paste curl commands directly into Yaak and it automatically formats them into the visual interface, bridging the gap between CLI and GUI workflows. API collections are stored as plain-text files for seamless Git integration and team collaboration.

Kreya is a privacy-first desktop API client designed specifically for teams working extensively with gRPC (Protobuf), though it also supports REST, WebSocket, HTTP/2, and HTTP/3. All data is stored locally on your machine in human-readable, Git-diffable files that integrate seamlessly with version control systems. Kreya excels in gRPC workflows with features like automatic protobuf compilation, service reflection, and streaming support.

The project-based workflow keeps API definitions organized and shareable through Git, while the local-first architecture ensures sensitive API keys and tokens never leave your machine. For teams building microservices with gRPC, Kreya provides specialized tooling that general-purpose API clients lack.

REST Client is a minimalist VS Code extension that lets you write HTTP requests in plain .http or .rest files, then send them with a single click or keyboard shortcut. This text-based approach means your API tests live alongside your code as version-controlled files, can be reviewed in pull requests, and are readable by anyone without special tools. It's perfect for developers who prefer code over clicking—write requests in a simple DSL, commit them to Git, and share them with your team. The simplicity is the selling point: no collections to manage, no accounts to create, just plain text files that do exactly what they say.

curl is the legendary command-line tool for transferring data using URLs, supporting dozens of protocols including HTTP, HTTPS, FTP, SFTP, and more. Installed by default on virtually every Unix-like system (macOS, Linux) and Windows 10+, curl is the universal language of API testing—every developer knows it, every platform supports it, and every API documentation includes curl examples. While it lacks the visual interface and advanced features of dedicated API clients, its ubiquity and scriptability make it irreplaceable for automation, CI/CD pipelines, debugging production issues via SSH, and quick one-off API calls. For developers who live in the terminal, curl is the fastest path from question to answer.