If you can tolerate the evaluation watermark on your exported images, you can use the official version downloaded directly from the StarUML website indefinitely. This keeps your system entirely safe from malware. Apply for Educational Discounts

Both licenses are — you pay once and can use that version forever. If you want to upgrade to a new major version (e.g., from V7 to V8), an upgrade fee applies.

StarUML provides a during which you can use the software with all features enabled. During this evaluation period, any diagrams you export will include watermarks. After the 30 days expire, you must purchase a license to continue using the software.

A highly popular web-based and desktop tool that features extensive drag-and-drop shapes for UML, flowcharts, and network architecture. Cost: Completely free with no feature restrictions.