There are numerous free diagramming applications such as LucidChart, which is a Web-based alternative to Microsoft Visio that features a drag-and-drop interface for drawing almost any conceivable diagram. Additionally, LucidChart can be used collaboratively with other team members. It even allows exporting and importing of .vdx files, the type of file used by Visio. Giffly is another Web-based diagramming tool. Like LucidChart, it offers flexible tools for a number of diagrams and can be used collaboratively by teams.
Dia, Diagramly and Pencil Project are all free diagramming tools available for download. Each of them functions very similarly to Microsoft Visio, particularly Dia. Like the Web-based tools, these downloadable application offer very flexible diagramming functionality. Regular users may prefer a local application; however, Dia, Diagramly and Pencil Project lack the collaborative tools offered by the two in-browser tools.
Many word processing and other productivity applications feature limited diagramming functionality. Microsoft Word and Powerpoint both include drawing and diagramming tools that can be used at no additional cost to users who already own the applications. Similarly, LibreOffice and OpenOffice, two free alternatives to the Microsoft Office suite, both include applications called Draw. Finally, Google Drive users can create diagrams by selecting New and then Google Drawing.