Postwoman: An Open‑Source Browser‑Based API Testing Tool – Features, Installation, and Usage

Postwoman is an open‑source Postman replacement that runs directly in the browser, offering a lightweight and convenient way to test APIs without installing heavyweight desktop clients.

Key features include support for GET, HEAD, POST, PUT, DELETE, OPTIONS, PATCH methods, request validation, real‑time response display, PWA capability, WebSocket testing, customizable UI, history tracking, collections, proxy support, pre‑request scripts, environment variables, and Docker integration.

Demo: https://postwoman.io

Source code is hosted on GitHub: https://github.com/liyasthomas/postwoman

Installation steps:

git clone https://github.com/liyasthomas/postwoman.git
npm install
npm run dev

# Or using Docker
# pull
docker pull liyasthomas/postwoman
# run
docker run -p 3000:3000 liyasthomas/postwoman:latest
# build
docker build -t postwoman:latest .

After starting the server, open a browser to access the interface; several screenshots illustrate the UI and common keyboard shortcuts such as Ctrl+G to send a request, Ctrl+S to save to favorites, Ctrl+K to copy the request link, and Ctrl+L to reset the request.

The author emphasizes that the browser‑based nature of Postwoman is especially useful for web developers, allowing cross‑platform testing without installation, and highlights that the tool is completely free and open‑source.