Eraser vs PlantUML (2026): which should you pick?

Pick Eraser if

• Fits if you're an engineer who'd rather type a diagram than drag boxes around
• Works for teams whose diagrams have to follow the code, since it reads a connected Git repo

Look elsewhere if

• Pricey if you just want a team whiteboard, at $45 a member a month billed annually or $60 monthly
• Tight if you're staying free, with 3 files, 3 AI credits, 7 days of history, no private files and no GitHub integration
• Watch out: AI past your monthly credits is $60 per 100, and API calls are billed on top of the plan
• Skip it if you need SAML SSO for a small team, as it's on Business Plus, $42 a member a month and sold from 10 seats
• Not for you if you want a desktop or phone app, as Eraser only runs in a browser

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

Eraser

• The Free plan stops at 3 files and 3 AI credits, keeps 7 days of version history and has no private files or GitHub integration.
• AI use beyond a plan's monthly credits costs $60 per 100 credits, and only on paid plans with usage-based pricing switched on.
• API calls are billed by usage on top of a paid plan: $80 per 100 prompt-to-diagram calls and $20 per 100 code-to-diagram calls.
• The vendor's site lists no desktop or mobile app; Eraser runs in a browser, and SAML SSO needs Business Plus, sold from 10 seats.

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.

Eraser

AI diagram generation

A prompt, an image or a file such as Terraform or a database schema is turned into an editable diagram, which can then be refined through AI chat or by hand in the visual editor.

Diagram-as-code

Architecture, sequence, flowchart, ERD and BPMN diagrams each have a text syntax, so a diagram can be read, compared and edited as code. It is included on every plan.

Canvas with Markdown notes

A file holds one infinite canvas and a note editor with Markdown support. Figures from the canvas can be embedded in the document, and files export to PDF, PNG, SVG or Markdown.

Codebase diagrams and Eraserbot

Diagrams can be generated from a connected Git repository. Eraserbot watches chosen files and comments on pull requests with updated diagrams when they change.

REST API and MCP server

The API renders a diagram from a prompt or from Eraser's diagram code. The MCP server lets Claude, Cursor or ChatGPT create, search, update and export diagrams.

Real-time collaboration and guests

Members edit together in real time and leave comments and mentions. Guests are free on every plan and can edit or comment only on files they are invited to.

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.

Eraser

• Free$0

  3 files, 3 AI credits and 7-day version history, with unlimited guests, diagram-as-code and Markdown notes.

• Business$45

  per member / month, billed annually ($60 billed monthly)

  Unlimited files, 100 AI credits a month, unlimited version history, private files, 100 custom icons, 1 Git repo and 1 data source.

• Business Plus$42

  per member / month, billed annually, minimum 10 seats

  Everything in Business, plus 250 AI credits a month, 3 Git repos and 3 data sources, SAML SSO and unlimited custom icons. Sold from 10 seats.

• EnterpriseCustom

  Unlimited AI credits, Git repos and data sources, custom hosting, SCIM, SIEM logging, a customer success manager and payment by ACH or wire.

PlantUML

• Open source$0

  Free jar and source code under your choice of license; you run it yourself or use the online editor.

Eraser

• Annual discount

  25% less with annual billing

  Business is $45 per member a month billed annually against $60 billed monthly, 25% cheaper. Business Plus is sold on annual billing only.

• Education

  Education discount on request

  Eraser's docs say discounts are available to education users, who request one by filling out a form. The size of the discount is not published.

• Nonprofit

  Nonprofit discount on request

  Non-profit users can request a discount through the same form linked from the pricing page FAQ and the docs. The size of the discount is not published.

PlantUML

No public discounts listed.