Eclipse Papyrus vs UMLet

Eclipse Papyrus is a free modeling environment for UML and related extensions, with desktop and web options. It lists implemented standards including UML 2.5, SysML 1.6, fUML 1.3, ALF 1.0.1, MARTE 1.1, PSCS 1.1, PSSM 1.0, and ISO/IEC 42010. Teams can tailor profiles, model explorers, diagram notation and style, properties views, palettes, and creation menus. With Moka, models can run through animation and simulation. Papyrus-Web supports simultaneous work on a shared model in a browser, with changes visible to stakeholders; its editors cover diagrams such as class, component, use case, activity, state machine, and communication. Desktop downloads are listed for 64-bit Windows and Linux, as well as Intel and Apple Silicon macOS. Papyrus requires a Java 21-compatible JVM and is released under the Eclipse Public License v2.0. Related tools provide code generation and reverse engineering in C++, C, Java, and Python, plus documentation generation for LibreOffice, Word, and PDF. Papyrus-Web can be tested locally with Rancher Desktop or Docker Desktop, with deployment documentation linked.

UMLet is a free, open-source tool for quickly sketching UML diagrams, including class, use case, sequence, state, deployment, and activity diagrams. Users edit diagram elements by changing text in a small markup dialect rather than configuring pop-up dialogs. UMLet is available as a stand-alone desktop application, an Eclipse plugin, the browser app UMLetino, and a Visual Studio Code extension. The desktop application exports to BMP, EPS, GIF, JPG, PDF, PNG, and SVG, can copy diagrams to the clipboard, and supports command-line batch conversion of UXF files. UMLetino runs in a browser without installation, stores diagrams in browser storage, and exports PNG. Custom elements can be made with Java code that UMLet compiles on the fly, but only in the stand-alone version. The desktop application requires Java and runs on Java platforms such as Windows, Linux, and macOS. UMLet identifies its license as GNU GPL 3.0. It does not generate code from models or reverse-generate models from code; round-trip engineering is not planned.