PlantUML vs. ToDiagram - Which Diagram Tool Fits Your Workflow?

Aykut Saraç

February 13, 2025

PlantUML is known for generating UML diagrams from text, but it also supports JSON visualization. Meanwhile, ToDiagram is designed specifically for working with structured data like JSON, offering an interactive, editable approach. In this post, we’ll compare both tools for JSON visualization.

JSON Visualization in PlantUML

PlantUML allows users to render JSON data into diagrams using its @startjson syntax. This feature converts JSON structures into tree-like representations, making them easier to interpret than raw text.

@startjson
{
  "name": "John",
  "age": 30,
  "address": {
    "city": "New York",
    "zip": "10001"
  }
}
@endjson

Pros:

✔ Integrates well with version control
✔ Supports text-based workflows
✔ Can generate static tree structures

Cons:

✘ No direct editing of diagrams
✘ Requires knowledge of PlantUML syntax
✘ Not optimized for large or complex JSON files

Handling Large JSON Files

PlantUML can process large JSON files, but it struggles with deeply nested or high-volume data. The more complex the JSON, the harder it becomes to read, and modifying the structure requires manually updating the text file. Since diagrams are static, navigating large datasets can be cumbersome. PlantUML has a default limit for image width and height, which is 4096 pixels. Unlike ToDiagram, you cannot collapse or expand nodes in PlantUML, making it harder to visualize large JSON files.

PlantUML diagram visualization

JSON Visualization in ToDiagram

ToDiagram is built for visualizing and editing JSON as interactive diagrams. It automatically converts JSON into a tree structure while allowing users to modify data directly.

Features

• Diagram editing: Edit JSON data directly on the diagram.
• Live updates: Any changes reflect instantly.
• Supports large JSON files: Handles bigger datasets smoothly.

Pros:

✔ No syntax learning required
✔ Fully interactive and editable
✔ Supports additional tools like JSON Schema generation

Cons:

✘ Not scriptable like PlantUML
✘ Requires a web interface or extension

Handling Large JSON Files

ToDiagram is optimized for large JSON files, making it easier to navigate and edit complex data. The interactive tree structure allows users to collapse or expand nodes, making it easier to focus on specific parts of the JSON. It also chunks large arrays into smaller sections, improving performance and readability.

ToDiagram diagram visualization

Key Differences

Which One is Right for You?

• If you want to script JSON visualizations and integrate with version control, PlantUML is a good choice.
• If you need an interactive editor that makes JSON easier to modify, ToDiagram is the better option.

Both tools can visualize JSON, but ToDiagram provides a more flexible, real-time editing experience, making it ideal for working with large and complex data.

Try Todiagram Editor for free.