UML Diagram StudioUML Studio

Structural UML

Object Diagram Maker

Draw an object diagram when you need a snapshot of instances, not just types. Start from the template, fill in example values, and export when the scenario is obvious to your readers.

Features

  • Live editor for object diagram maker
  • Starter template included on the page
  • PNG and SVG export
  • No install required

Need a blank canvas? Open the full UML studio.

What you can model

Object diagrams show concrete instances, attribute values, and links at a moment in time. Use them for fixtures, sample payloads, onboarding examples, and runtime explanations that a class diagram alone cannot make vivid.

How to use this maker

Edit the PlantUML in the editor. Create an object block for each instance, set only the attribute values that matter to the story, draw links between instances, watch the preview, then download PNG or SVG.

Notation that matters

Name instances clearly (user1: User). Show attribute values inside the object. Links usually mirror associations from your class model. Keep type names consistent with the class diagram so readers can map example to type.

Keep the diagram readable

Limit the scenario to one story, such as a single order with a few line items. Drop attributes that do not change the explanation. Prefer the class diagram maker for type structure and a sequence diagram when message order is the question.

Frequently asked questions

Is this object diagram maker free?

Yes. You can create and export diagrams in the browser without a paid plan.

When should I use an object diagram instead of a class diagram?

When stakeholders need a concrete example with real values, not only the abstract type model.

Can I work entirely online?

Yes. This page is a browser editor with live preview. No desktop install is required for everyday drafting.

Related tools

Browse the full UML diagram tools directory or return to the UML diagram hub.