The Best PlantUML Alternatives in 2026

Kroki provides one API for generating diagrams from textual descriptions using libraries such as Mermaid, PlantUML, Graphviz, and D2.

PlantText provides an online editor for PlantUML code and generates class, sequence, activity, and state diagrams.

SankeyMATIC builds flow diagrams for comparing quantities across stages, with examples covering budgets, results, and processes.

DiagramGPT generates diagrams from text prompts, with the project page describing diagram workflows for teams.

Tree generates ASCII diagrams of folder structures as a browser utility written in TypeScript and React.

Mermaid generates diagrams such as flowcharts and sequence diagrams from text using syntax similar to Markdown.

Flowchart Fun generates flowcharts and diagrams from text through a web application.

Dia is free, open source drawing software for structured diagrams, with downloads, shapes, and documentation.

Swimlanes.io creates sequence diagrams from text in a browser and lets users download diagrams or share them through links.

UMLet provides free, open source UML drawing with a simple interface for making diagrams, including sequence and activity diagrams.

Graphviz creates diagrams from graph descriptions and provides open-source software for visualizing structural information.

Mermaid Live Editor creates charts and diagrams from text using Mermaid’s markdown-like syntax in a browser.

Flowchart Fun converts text into flowcharts, mind maps, and process diagrams through an online text-based editor.

JDL-Studio draws UML diagrams from JDL syntax and provides instant feedback with customizable styling.

In a browser, yEd Live supports diagram creation, import, editing, and automatic arrangement for free.

text2diagram creates diagrams and charts from text descriptions, with real-time collaboration and document permissions listed on its page.

Cascii Core builds ASCII and Unicode diagrams in a browser using vanilla JavaScript, without server or library dependencies.

Kroki CLI converts diagram files through the Kroki service, inferring diagram type from the file extension by default.

draw.io provides a free, open source application for creating diagrams, with storage options chosen by each team.

JSON Crack is an open source visualization application that turns JSON, YAML, XML, and CSV data into interactive graphs.

QuickChart generates chart images through an API that can embed visualizations in emails, reports, and other platforms.

Line Graph Maker builds customizable line charts from labels and data values, with image export available from the page.

amCharts lets users build interactive charts and maps in a browser from templates, then export, embed, or publish them.

Edotor provides a web-based editor for creating and editing Graphviz diagrams.