AI diagram generator

UML Diagram Generator

Generate uml diagrams in seconds. Describe what you need in plain English – or paste in code – and Eraser draws it.

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How it works

How to generate an uml diagram

Tips on generating a UML diagram
  • Instead of writing a prompt from scratch, consider pasting excerpts from existing existing documentation, product code, system output, project description, or uploading image files.
  • Working with an LLM to create a fleshed out diagram prompt can be effective. Specify to the LLM the type of UML diagram and system or flow that you’re trying to visualize, and ask it to create a list out what should be shown on the diagram.
Example diagrams
  1. 1

    Determine the type of UML diagram you’d like and specify that in the prompt

    For example, start the prompt with “Generate a sequence diagram”. UML diagram types include:

    • Class Diagram (supported by Eraser)
    • Use Case Diagram (supported by Eraser)
    • Sequence Diagram (supported by Eraser)
    • State Diagram (supported by Eraser)
    • Activity Diagram
    • Component Diagram
    • Deployment Diagram
    • Object Diagram
    • Package Diagram
    • Communication Diagram
    • Interaction Overview Diagram
    • Timing Diagram
  2. 2

    Describe the content of the diagram

    A simple one-liner can work too but the best prompts are usually at least 3-4 sentences long. Here are some helpful prompting frameworks for each UML diagram type:

    • Class Diagram: First, write out the entities (i.e. tables). For the entities, you may want to specify attributes (i.e. columns) and their data types. You can also specify primary and foreign keys. Then, write out the relationship between tables including the relationship cardinality.(e.g. “the user entity and the document entity have a one-to-many relationship via the userId attribute”)
    • Use Case Diagram: Make sure to describe users (e.g. student, teachers) and use cases (e.g. submit homework, view grades). Include the visual requirements of a use case diagram to the prompt: “A use case diagram consists of users and use cases. Users are rectangle shapes and use cases are oval shapes. Connections between users use cases show what users have what use cases, don’t add any other connections. Put use cases in a group called use cases. Don’t put users in a group and don’t group use cases by users. Mention “Use Case Diagram” in the title.”
    • Sequence Diagram: Write a prompt describing a user flow or a data flow as a sequence of events. Structuring the prompt as a numbered list maps well to a sequence diagram.
    • State Diagram: Make sure to describe states (e.g. logged in, logged out) and transitions (e.g. submit credentials, session expiry). Include the visual requirements of a state diagram to the prompt: “States are circle shapes. And connections represent the transition between states. Use icons as appropriate.”
  3. 3

    Generate a diagram with the completed prompt

  4. 4

    Edit the diagram with follow-up prompts (this step requires signing in to Eraser)

  5. 5

    Manually adjust the layout using GUI controls (this step requires signing into Eraser)

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Generate any type of diagram with AI

FAQ

Frequently asked questions

  • Can I edit the generated uml diagram?

    Yes. Click “Save and Edit Diagram” to open it in Eraser, where you can edit using diagram-as-code syntax or the visual GUI.

  • What can I use as a prompt?

    Plain English, a nested list, or a code snippet. You can also paste excerpts from requirements docs, transcripts, or knowledge-base articles.

  • Can I use this from an AI agent?

    Yes. Eraser runs an MCP server, so any MCP-compatible client – Claude, Cursor, or ChatGPT – can create and edit these diagrams directly. See the MCP catalog for what it exposes.

  • Who created this tool?

    The uml diagram generator was created by the team at Eraser, leveraging frontier AI models. Eraser is an AI tool for technical design and documentation.

  • Is it free?

    Generating an uml diagram is free and requires no sign-up. Sign in to a free Eraser account to edit, save, and export your diagrams.

  • Is there an API?

    Yes, you can read our API documentation. The API is only available to Starter, Business, and Enterprise Plan teams.

  • Is there an MCP server?

    Yes. The Eraser MCP server lets an agent create, search, read, update and export diagrams from clients like Claude, Cursor, VS Code and ChatGPT. It is free to use, subject to the AI credit limits of your plan.

  • Do you use my data to train AI models?

    No. Neither Eraser nor our model providers use your data to train AI models. Eraser may analyze usage to improve and enhance our AI features.

  • How do I get started?

    Describe what you need in the prompt box above and generate. You can keep refining the result with follow-up prompts.

  • What’s next for this tool?

    It only gets better from here. We’re working to improve accuracy and layout customization. If there’s something you’d like to see, drop us a note at hello@eraser.io.

  • How do I get in touch?

    We’d love to hear from you. Reach out at hello@eraser.io, on X (@eraserlabs), or join our Slack community.