Umbrello
Model application relationships and behaviour visually before implementing a complex feature.
What’s included for free?
Free open-source UML modelling software. KDE provides Linux installation and Windows packages; nightly versions are for testing. It is a modelling tool rather than an application builder or hosted collaboration service.
Where it runs: Local install
Provider information ↗Checked 2026-10-16
Before you use it
GPL-2.0-or-later software; redistribution and modifications must follow source and licence obligations. User-created content has separate rights.
Provider terms can change. Check current pricing and usage rights before starting a project.