Graphviz Alternatives

PlantUML is an open-source tool that uses simple textual descriptions to draw UML diagrams.

Gephi is an open-source software for visualizing and analyzing large networks graphs.

Dia is a GTK+ based diagram creation program for GNU/Linux, MacOS X, Unix, and Windows, and is released under the GPL license.

yEd is a free desktop application to quickly create, import, edit, and automatically arrange diagrams. It runs on Windows, Mac OS X, and Unix/Linux.

Online diagramming application

OmniGraffle is for creating precise graphics like website wireframes, an electrical system designs, or mapping out software class.

LucidChart is the missing link in online productivity suites. LucidChart allows users to create, collaborate on, and publish attractive flowcharts and other diagrams from a web browser.

KeyLines is a powerful network visualization toolkit. Build products with game-changing interactive visualization that turns data into insight.

Draw, LibreOffice, ODF, open standards, creative software, vector drawing

Search and visualize your graph data through a simple web-based interface

An easy tool for generating diagrams and flowcharts from text in a similar manner as markdown.

Cytoscape Official Web Site