Which UMLet Version Should I Use: Standalone, Eclipse Plugin, Web App, or VS Code Extension?

UMLet ships in four forms, and the right one depends on where you already work. Choose the stand-alone app if you want the full feature set on Windows, macOS, or Linux without an IDE; the Eclipse plugin if you model inside Eclipse; the web app (UMLetino) if you need a diagram fast without installing anything; and the VS Code extension if Visual Studio Code is your editor. All four share the same core idea — you edit UML elements as text rather than through pop-up dialogs — so the choice is mostly about environment, not diagram capability.

The four options at a glance

Stand-alone app

This is the reference version. The site calls it the "full-featured UMLet as stand-alone app for Windows, macOS, and Linux," which makes it the default choice when you don't have a strong reason to stay inside an IDE.

Pick it if you want the complete toolset — custom elements, the full export range, and the sample palettes — in one place. The trade-off is that it's a separate program, so you switch windows instead of drawing next to your code.

Eclipse plugin

Choose this if Eclipse is already your development environment. The plugin keeps diagrams inside the IDE, so you avoid context-switching between a project and a separate diagramming tool.

The site notes that version 14.3 improved "OS and Eclipse integration," so the plugin has received specific attention rather than being an afterthought. If you live in Eclipse, this is the natural fit.

Web app (UMLetino)

UMLetino is the browser version, and it's the right pick when installation isn't an option — a locked-down machine, a quick diagram on someone else's computer, or a sketch you want to share without a file.

It has grown more capable over time. Version 15.0 added zoom, lasso selection, export, dark mode, hi-res export, and startup improvements. That covers most sketching needs, though a browser tool is generally the lighter option compared with the stand-alone app.

VS Code extension

Use this if Visual Studio Code is your editor. It puts UMLet's text-driven element editing inside the editor you already have open, which suits developers who want diagrams to live alongside source files.

The extension is listed on the VS Code Marketplace, and the site invites users to "star it" there — a small signal that it's actively maintained rather than abandoned.

What's the same across all four

The core workflow doesn't change with the version:

• Add elements with a double click.
• Edit elements in the lower-right text panel, using a small markdown-like dialect instead of dialogs.
• Get help with Ctrl+Space for context-sensitive assistance.
• Select multiple elements with Ctrl or a lasso.
• Copy to clipboard by pressing C.
• Zoom with +/− or Ctrl+mousewheel.
• Hold Shift to avoid sticking relations.

Diagram type support is also shared: class, use case, sequence, state, deployment, and activity diagrams. Custom elements — where you change a few lines of Java and UMLet compiles the new element on the fly — are part of the tool's design, so if that's your reason for using UMLet, confirm the specific version supports the workflow you need before committing.

How to decide

• No IDE preference, want everything: stand-alone app.
• Work in Eclipse: Eclipse plugin.
• Can't or don't want to install: UMLetino in the browser.
• Work in VS Code: VS Code extension.

If you're unsure, start with the stand-alone app to learn the text-editing workflow, then move to the plugin or extension that matches your daily environment. The skills transfer directly because the element syntax is the same.

A note on cost and support

The site describes UMLet as "a free, open-source UML tool." It also lists sponsorship options via GitHub, Patreon, and PayPal, and provides contact at [email protected] plus a code ticket system for bugs and requests. Sponsorship is optional support for the project, not a paid tier — the page presents the tool itself as free and open-source.