Yes, there are several free and open-source wireframing tools available for designers. Some of the popular options include, Pencil Project, Wireframe.cc, Mockplus, Figma (free plan), Balsamiq Wireframes, and so on.  These tools provide designers with the ability to create wireframes and prototypes quickly and easily, without the need for expensive software or a steep learning curve. They offer a range of features and UI elements, making them suitable for a variety of design projects.