Top Alternatives to Gliffy

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.

Pencil Project is an open-source GUI prototyping tool.

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.

ConceptDraw PRO is diagramming software used to create business graphics, including ConceptDraw Flowcharting Suite.

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.

Moqups is a streamlined and intuitive web app that helps you create and collaborate on wireframes, mockups, diagrams and prototypes for any type of project.

PlantUML is an open-source tool allowing users to create UML diagrams from a plain text language.

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

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

Axure RP is a wireframing, rapid prototyping, documentation and specification software tool aimed at web and desktop applications.

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

Grafio is a fun and capable diagraming app for iOS with plenty of features at a fraction of the cost of others.

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

Fluid UI is a browser-based wireframing and prototyping tool developed by Fluid Software and used to design mobile touch interfaces.

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.

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.

Nevron Draw is a software for creating flowcharts and diagrams.

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