nomnoml vs PlantUML (2026): which should you pick?
As of Nov 13, 2026, PlantUML grades higher than nomnoml: 3.0 against 2.8 out of 4.0.
Checked Nov 12, 2026 and Nov 13, 2026 · graded Nov 12, 2026 and Nov 13, 2026 by ToolGPA
PlantUML grades higher on platforms. They get the same grade on value for money, the free plan, features and ease of use.
Price, platforms and features side by side. The table says where each price was read and when.
Which one is for you
Pick nomnoml if
- Fits if you want a class or flow diagram out of a few lines of text
- Works for developers who embed diagrams through the library or command line
Look elsewhere if
- Skip it if you want a freehand canvas or sticky-note board
- Watch out: saving relies on browser localStorage, which the author says comes with no guarantees
- Not for you if you need accounts, sharing links or real-time editing, as the web app has none
- Too light for teams: no collaboration of any kind is listed
Pick PlantUML if
- Fits if you want diagrams stored as text next to your code
- Works for teams documenting systems in wikis or Markdown
Look elsewhere if
- Skip it if you want to drag shapes around a canvas
- Not for you if you sketch freehand, because it has no whiteboard
- Watch out: layout is decided by the engine, so fine control over placement is limited
- Watch out: only the GPL build has every feature, and other license builds lack some such as ditaa
How we grade them
| 2.8GPAnomnomlGood | 3.0GPAPlantUMLVery good | |
|---|---|---|
| Value for money | AFree, open source and available as a library and a command line tool as well as the web app. | AFree and open source, with a jar anyone can download or an online editor. Nothing to pay, whatever the category's $5 to $10 a month. |
| Free plan and trial | AFree outright, with no sign-up, cap or paid plan. | AThe whole tool is free, under GPL, LGPL, Apache, BSD, EPL or MIT licenses, so there's no cap to hit. |
| Features | CClass, component and flow diagrams from text, with styling. It does that fully, but it is a smaller job than a whiteboard, with no freehand canvas or sticky notes. | CUML plus Gantt, mind maps and wireframes from text. But the FAQ admits you get less say over layout, there's no visual canvas, and non-GPL builds lose some features like ditaa. |
| Ease of use | CNo store rating on record. You learn its text syntax first. | CYou have to learn its text language before you get a diagram, and no store rating is on record. The in-browser editor takes some of the sting out. |
| Platforms and integrations | CWeb only for most people, plus a library and command line. No integrations are listed. | BRuns in a browser and through a jar, with links into Confluence, MediaWiki, IntelliJ IDEA, Eclipse and GitHub. No phone app or desktop app of its own is listed. |
| Best for | UML diagrams drawn from a text syntax | text-described UML and other diagrams |
The GPA is the average of the five grades: an A is 4 points, an F is none. The full reasons are on each tool's page: nomnoml and PlantUML. How we grade
Price against what you get
nomnoml has no paid plan and scores 2.0 out of 4 on features, ease of use and platforms. PlantUML has no paid plan and scores 2.3.
PlantUML scores higher for the same starting price. Of the other whiteboard and mind map tools on the chart, none scores higher than nomnoml for less, and none scores higher than PlantUML for less.
Features, ease of use and platforms, averaged
What paid plans start at, a month (each step along is roughly double) →
- The best score at each price
- Has a free plan
- No free plan
Where they differ
- PlantUML also covers Gantt & timelines and mind mapping.
In commonFree planWebOpen sourceDiagrams
At a glance
| nomnoml | PlantUML | |
|---|---|---|
| Pricing | Free | Free |
| Starts at | Free | Free |
| Free plan | None | Free of charge and open source, under several license options including GPL, LGPL, Apache, BSD, EPL and MIT. |
| Free trial | None listed | None listed |
| Web | ||
| Browser extension | ||
| Made by | Daniel Kallin | PlantUML |
| Price read from | nomnoml.com | plantuml.com |
| Checked | Nov 13, 2026 | Nov 12, 2026 |
Worth knowing
nomnoml
- It draws diagrams from code only; there is no freehand canvas or sticky-note board.
- Saving relies on browser localStorage, which the author says comes with no guarantees.
- The web app has no accounts, sharing or real-time collaboration.
PlantUML
- Layout is controlled by the engine; the FAQ says it gives less control over placement than drag-and-drop tools.
- Diagrams are written in code, so there is no visual canvas for freehand sketching.
- Builds under licenses other than GPL lack some features, such as the ditaa integration.
Key features
nomnoml
- Text syntax with live preview
- Edit the code on the left and the diagram on the right updates as you type, with keyboard shortcuts borrowed from Sublime Text.
- Several UML shape families
- Built-in classifier types cover classes, abstract classes, packages, components, sockets, actors, use cases, states, choices, databases and tables.
- Styling directives
- Directives such as #direction, #fill, #font and #spacing change layout and appearance, and custom classifier styles can be defined and imported from other files.
- Library and command line
- The nomnoml npm package renders diagrams on a web page or to SVG in Node, and npx nomnoml converts a file from the command line.
- Browser-only storage
- The web app is client-side and keeps your diagram in the browser's localStorage, so it is there on your next visit, though the author gives no guarantee.
PlantUML
- Text-to-diagram language
- Diagrams are written as short text and drawn from it, so changing the text updates the picture.
- UML and non-UML diagrams
- Supports sequence, use case, class, object, activity, component, deployment, state and timing diagrams, plus Gantt, MindMap, WBS, wireframe and others.
- In-browser editor
- The home page has an editor that runs in the browser with a JavaScript rendering engine and redraws as the code changes.
- Many integrations
- The Running page lists connections to wikis and forums, editors and IDEs, including Confluence, MediaWiki, IntelliJ IDEA and Eclipse.
- Several license options
- The download page offers jars under GPL, LGPL, Apache, BSD, EPL and MIT; the GPL build is the one with every feature, such as ditaa.
Plans
nomnoml
Free$0
The whole editor, the npm library and the command-line renderer are free under the MIT license.
PlantUML
Open source$0
Free jar and source code under your choice of license; you run it yourself or use the online editor.
Common questions
Which is cheaper, nomnoml or PlantUML?
As of Nov 13, 2026, both nomnoml and PlantUML are free to use.
Which has a free plan, nomnoml or PlantUML?
As of Nov 13, 2026, both nomnoml and PlantUML have a free plan.
Which platforms do nomnoml and PlantUML run on?
As of Nov 13, 2026, only PlantUML lists a browser extension. Both list a web app. A platform missing from a listing is one its maker's pages did not mention.
More comparisons
How this page was made
- The verdict at the top follows a fixed rule. When both tools are in the same category and either is in our top three for it, the verdict follows that ranking: the higher-placed tool is our pick. The top three weigh who each tool suits as well as its grades, so a pick can go against the GPA. Otherwise the page does not pick one and says which grades higher: the higher GPA first; on a tie, the one with a free plan, then the one that starts cheaper in dollars a month, counted the same way for both; if they are still level, what the choice depends on.
- The grades are our own, from each tool’s review or report card. The GPA is their average.
- Prices, plans and platforms come from each tool’s listing. The table above says where each price was read and when.
- The differences and the answers to the questions are worked out from those listings.