PlantUML online

PlantUML online, as editable shapes.

Use LetDraw as a PlantUML online editor: paste PlantUML text and get a hand-drawn diagram you can actually change. Drag boxes, restyle arrows, add comments and share a link. The text is read right in your browser, with no render server involved.

Paste PlantUML How it works
shop.puml · component view
Shop User uses REST stores Web component API component Orders Packages become frames. Labels after ":" stay on arrows.
Step by step

How to open PlantUML online in LetDraw

From a .puml file to a shareable, editable diagram in a minute, right in your browser.

  1. Open Generate from Code

    In LetDraw, open Generate from Code (a Pro feature) from the More menu or the command palette.

  2. Paste your PlantUML

    Paste text that starts with @startuml, or load a .puml or .plantuml file. The format is detected and a live preview appears.

  3. Pick a layout

    Choose top-down or left-right, a clean or sketchy style, and hide relationship labels you do not need.

  4. Insert and share

    Insert it onto the canvas, edit it like any drawing, share a link or export it as PNG, SVG or PDF.

PlantUML to editable diagram

A PlantUML editor where the output is yours to change

LetDraw reads elements such as actor, component, class, interface, database and node, along with the relations between them, and lays them out as shapes and arrows. Component, deployment, class, use case and state diagrams map best; sequence messages become labelled arrows between participants.

  • Packages become frames, and so do namespaces, rectangles and frames
  • Relation labels kept, so the text after a colon stays with its arrow
  • Export to Mermaid or D2 when you want the diagram as code again
Try it now
@startuml actor User package "Shop" { [Web] [API] } User --> [Web] [Web] --> [API] : REST User Shop Web REST API
What people draw

Why open your PlantUML files in LetDraw

Keep writing text where it helps, and switch to a canvas when people need to see, discuss and change the picture.

Migrating old docs

Bring .puml files from a wiki or repo onto a canvas where anyone can edit them without a toolchain.

Component views

Turn component and deployment diagrams into an architecture sketch you can rearrange for a review.

Use case workshops

Start from the actors and use cases you wrote, then add ideas live with the people in the room.

State diagrams

Paste states and transitions and get labelled arrows you can tidy and annotate.

Team reviews

Share the board, pin comments to any point and edit together in real time.

Class overviews

See how classes and interfaces relate at a glance, then add the details that matter by hand.

Questions

PlantUML online FAQ

Is PlantUML online in LetDraw free?
Generate from Code, which turns PlantUML text into a diagram, is included in Pro. Drawing by hand, templates, shape libraries and export to PNG, SVG and PDF are free on the Free plan, with no credit card.
Which PlantUML diagrams are supported?
Component, deployment, class, use case and state diagrams, plus sequence diagrams in a simplified form where each message becomes a labelled arrow. Gantt, mind map, WBS, salt, JSON and YAML diagrams are not supported yet.
Is my PlantUML sent to a render server?
No. LetDraw does not use a PlantUML server; it reads the text in your browser and builds the diagram with its own layout, so positions can differ from a PlantUML render.
What happens to class members and notes?
They are skipped: each class becomes a box with its name, and notes are left out. Once the diagram is on the canvas you can add text, tables or comments wherever you need them.

More ways to diagram from code

Terraform diagrams Helm chart diagrams Graphviz DOT SQL to ER diagram OpenAPI visualizer Git graph EXPLAIN plan visualizer UML diagrams

Your PlantUML, ready to edit.

Open LetDraw in your browser, paste PlantUML and get shapes you can move. Fast, and nothing to install.