The best free alternative to Creately is diagrams.net, which is both free and Open Source. If that doesn't suit you, our users have ranked more than 50 alternatives to Creately and many of them is free so hopefully you can find a suitable replacement. Other interesting free alternatives to Creately are yEd Graph Editor (Free), LibreOffice - Draw (Free, Open Source), Dia (Free, Open Source) and PlantUML (Free, Open Source).
Cacoo is a user-friendly online diagramming tool that allows you to create a variety of diagrams such as wireframes, flowcharts, UML diagrams, network diagrams, mindmaps, sitemaps, database diagrams, and more.
The PlantText tool is an online tool for quickly creating UML (Unified Modeling Language) diagrams. Unlike most tools, PlantText can build diagrams without the use of a mouse because it is based on PlantUML markup language.
Clickcharts flowchart software allows for easy drawing of diagrams and flowcharts to provide a way of organising and displaying data. Lay out your ideas, organisation and processes or create UML, Venn or mind map diagrams with this flow diagram maker.
PathVisio is a free open-source pathway analysis and drawing software that allows drawing, editing and analysing biological pathways. It provides a basic set of features for pathway drawing, analysis and visualization. Additional features as plugins.