Open-source Apidog alternatives

Hoppscotch is an open-source API development ecosystem for sending requests, inspecting responses and organizing API work. It is positioned as an alternative to Postman and Insomnia and runs in the browser, as a desktop app and from a command line interface, with offline, on-premises and cloud options.

The request builder supports the standard HTTP methods plus custom ones, and the toolset extends to GraphQL and WebSocket testing. You can generate code snippets for more than ten languages and frameworks, share requests through public URLs, and install the web app as a progressive web app for offline use. The interface is lightweight, with light, dark and black themes, a choice of accent colors and a distraction-free Zen mode.

Hoppscotch is MIT licensed and written mainly in TypeScript with Vue. Teams that need to keep API traffic and collections inside their own network can self-host it, while the hosted service at hoppscotch.io suits individuals who just want to start sending requests.

Bruno is an open-source API client and testing environment, described as a lightweight alternative to Postman and Insomnia. It supports REST, GraphQL, gRPC and WebSocket requests, and runs on macOS, Windows and Linux.

Its distinguishing idea is that collections live directly in a folder on your filesystem, saved in a plain text markup language called Bru. That means you can version and share API collections with Git or any version control system you already use. Bruno is offline only, and the maintainers state they have no plans to add cloud sync, because they believe your data should stay on your device. A CLI runs collections from the command line for automated testing and CI/CD, and a Docker option is also documented.

The core is MIT licensed, and the project offers paid versions that add further features for teams that want them. Bruno can be installed from the website or through Homebrew, Chocolatey, Scoop, Snap, Flatpak and Apt. It suits developers who prefer keeping API definitions next to their code.

Insomnia is an API client from Kong that is open source and runs on every major desktop platform. It handles GraphQL, REST, WebSockets, Server-Sent Events, gRPC and other HTTP-compatible protocols, so one desktop app can cover most of the API work a developer does day to day.

With it you can debug requests, design APIs in a native OpenAPI editor with visual preview, test them with native test suites and a collection runner, and mock them with a cloud or self-hosted mock server. A command line tool supports linting and testing in CI/CD pipelines, collaboration features help teams share work, and third-party plugins extend the app. Projects can be stored in a Local Vault for fully local use, synced through any Git repository, or kept in the cloud with optional end-to-end encryption.

Insomnia is Apache-2.0 licensed and written in TypeScript on Electron. It is free to get started with, and paid collaboration features are available from the vendor. It is a popular alternative to Postman for developers who want flexible storage options.

Voiden is an offline API client for developers, QA engineers, and technical writers to build, test, collaborate on, and document APIs in one place. APIs are described in plain-text .void files that you keep in Git, with no account and no required cloud sync. It is built with Electron and TypeScript and released under the Apache-2.0 license.

Requests are composed from reusable API blocks that can be replaced and versioned like code, with a slash-command interface and a command-line tool designed to work with AI agents. It supports REST, GraphQL, gRPC, and WebSocket protocols, imports OpenAPI, and topics mention an MCP client. The project says it has no telemetry, no venture funding, and no cloud lock-in.

Voiden is positioned as an alternative to Postman, Bruno, and Insomnia. It suits teams who want their API collections and documentation to live in the repository as files that can be reviewed and shared through normal Git workflows.

HTTPie Desktop is a desktop application for testing REST, GraphQL and general HTTP APIs, built by the team behind the HTTPie command-line tool. It is aimed at developers who want a graphical client for exploring and testing APIs rather than working purely from the terminal or a web-only tool.

The repository publishes prebuilt releases of the app for macOS, Windows and Linux, and the installed application auto-updates after the initial install. On Linux it is distributed as an AppImage, which the project recommends running through AppImageLauncher rather than executing directly. A web app version is also available at httpie.io/app or through the req.new shortcut.

The repository metadata lists the project's license as Other, so check the license terms before relying on it for commercial use. It is a packaged, closed-source-adjacent distribution of releases rather than a buildable open-source codebase in this particular repo, and users looking for ongoing feature changes should follow the release notes linked from the project.