Best Open Source UML Tools 2025

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Browse free open source UML tools and projects below. Use the toggles on the left to filter open source UML tools by OS, license, language, programming language, and project status.

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1

NClass

NClass is a free tool to easily create UML class diagrams with full C# and Java language support.

17 Reviews

Downloads: 81 This Week

Last Update: 2013-04-30
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2

EasyEnglishWords

We are planning to develop a higly useful program to learn english words in a nice and easy way.

Downloads: 0 This Week

Last Update: 2015-05-01
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3

Lemming Project 2000

Szoftverlab 4: Lemming jatek tervezese

Downloads: 0 This Week

Last Update: 2014-03-20
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