Hoppscotch

Hoppscotch is an open-source API development platform that provides a fast, lightweight alternative to Postman for testing and debugging APIs. It runs entirely in the browser with no installation required, making it immediately accessible to any developer who needs to make API calls. The platform supports a broad range of protocols beyond standard REST APIs, including GraphQL with schema introspection and query building, WebSocket connections for real-time communication testing, Server-Sent Events (SSE), MQTT for IoT protocol testing, and Socket.IO. This protocol diversity makes Hoppscotch more versatile than many API tools that focus exclusively on REST. The interface is clean and responsive, with request construction, response inspection, and history tracking that feels snappy even on modest hardware. Pre-request and post-request scripts allow developers to set up dynamic variables, chain API calls, and validate responses programmatically. Team collaboration features include shared collections, team workspaces, and environment management. Code generation produces client code in multiple programming languages from configured API requests, saving developers from manually translating curl commands into application code. The self-hosted option, available as a Docker deployment, gives enterprise teams the ability to run Hoppscotch within their own infrastructure, addressing data privacy and security requirements that prevent some organizations from using cloud-based API tools. Hoppscotch is best suited for developers who want a fast, no-nonsense API testing tool without the overhead of installing and running a desktop application. Its browser-based approach means it works on any operating system and is especially convenient for quick API testing tasks. Teams that value open-source software and want to avoid vendor lock-in will appreciate the transparent development and self-hosting option. Developers working with WebSocket, GraphQL, or MQTT protocols will find Hoppscotch's broad protocol support particularly useful. Hoppscotch is completely free and open-source under the MIT license. The self-hosted enterprise edition adds team management, admin controls, and audit logging. There are no AI features built into Hoppscotch currently, which may be a consideration for teams that value AI-assisted test generation and documentation features offered by competitors like Postman.