Balsamiq
Low-fidelity wireframing and prototyping tool for product teams
12 tools like Whimsical, chosen by what they do. About Whimsical

Low-fidelity wireframing and prototyping tool for product teams

Free infinite whiteboard for sketches and quick team collaboration

Free open source tool for GUI mockups and prototypes




AI diagram editor for flowcharts, sequences and system designs

Design system platform linking Figma, code, docs and AI agents

IBM's open source design system with components and guidelines


Open source image compressor that runs locally in your browser

Searchable library of app and website screens for design reference