Top Alternatives to PlantUML

Lucidchart is a web-based application to draw diagrams.

draw.io is free online diagram software for making flowcharts, process diagrams, etc

Dia is free and open source drawing software.

yEd is a free general-purpose diagramming program with a multi-document interface.

Microsoft Visio (formerly Microsoft Office Visio) is a diagramming and vector graphics application and is part of the Microsoft Office family.

OmniGraffle is a diagramming and digital illustration application for macOS and iOS.

Freeplane is a free, open source software application for creating mind maps and electronic outlines.

Mindomo is an online mind map Software where users can create, view and share mind maps in their browser.

MindMeister is a collaborative mind mapping software that allows its users to visualize their thoughts.

Creately is a collaborative diagramming and design software used by teams around the world to communicate more effectively.

TheBrain, formerly branded PersonalBrain, is a mind mapping and personal knowledge base software.

Visual Understanding Environment or VUE is a free, open source concept mapping application written in Java.

MindManager is a commercial mind mapping software application developed by Mindjet. The software provides ways for users to visualize information in mind maps and flowcharts.

Google Drawings is a free, web-based diagramming software developed by Google.

Graphviz (Graph Visualization Software) is a package of open-source tools initiated by AT&T Labs Research for drawing graphs specified in DOT language scripts.

Gliffy is software for diagramming via a HTML5 cloud-based app. It is used to create UML diagrams, floor plans, Venn diagrams, flowcharts and various other kinds of diagrams online.

Cacoo is a user friendly online drawing tool. Multiple users editing the same diagram means Real-Time Collaboration.

Gephi is the leading visualization and exploration software for all kinds of graphs and networks.

SmartDraw is the smartest way to draw any type of chart, diagram: flowcharts, org charts, floor plans, network diagrams, and more.

StarUML is an opensource UML tool.

Edraw Max is comprehensive mind mapping and planning tool network diagrams, floor plans, workflow diagrams, business charts, and engineering diagrams.

Umbrello UML Modeller is a free software UML diagram tool available natively for Unix-like platforms and Windows.

UMLet is an open-source Java-based UML tool designed for teaching the Unified Modeling Language and for quickly creating UML diagrams.

Visual Paradigm (VP-UML) is a UML CASE Tool.

Mock up an application and show what's important, the idea, the information, the interaction.

Software Ideas Modeler is a CASE and an UML tool.

Diagram Designer is a vector graphics editor that allows you to create UML class diagrams, illustrations, flowcharts and slide shows.

Diagramo is an online flowchart software. It's FREE and Open Source ( GPL ) It's pure HTML5 Share and collaborate.

ThinkComposer is a flexible visual tool, which allow users to create enriched diagrams based on their domain of knowledge.

Bonita BPM is an open-source business process management and workflow suite.

VisiTouch helps you view and convert to PDF your MS Visio diagrams for iPhone.

ProcessMaker is an Open source web-based workflow software and Business Process Management software.

Astah Community is a free software design tool which supports the latest UML diagrams.

Nevron Draw is a software for creating flowcharts and diagrams.

Diagrammix is a tool for efficiently building attractive diagrams and flowcharts.

WhiteStarUML is a UML modeling tool.