The best free alternative to ConceptDraw DIAGRAM is Excalidraw, which is also Open Source. If that doesn't suit you, our users have ranked more than 25 alternatives to ConceptDraw DIAGRAM and many of them is free so hopefully you can find a suitable replacement. Other interesting free alternatives to ConceptDraw DIAGRAM are LibreOffice - Draw, yEd Graph Editor, Dia and Pencil Project.
Excalidraw is an open-source whiteboard tool that lets you easily sketch diagrams that have a hand-drawn feel to them. Available directly online as a web app and also through CodeSandbox to easily see how the code works, and the app is available for self-hosting.
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Draw lets you produce anything from a quick sketch to a complex plan, and gives you the means to communicate with graphics and diagrams. With a maximum page size of 300cm by 300cm, Draw is a an excellent package for producing technical drawings, general posters, and much else.
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yEd is a powerful diagram editor that can be used to quickly create diagrams manually or import external data for analysis and auto-magically arrange even large data sets by just pressing a button. You can use yEd to quickly create flow charts, BPMN and UML diagrams...
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Open-source diagram editor supporting Linux, Windows, Unix, and Mac OS X, with features for constructing entity relationship, UML, flowchart, and network diagrams, customizable with XML-defined shapes, extensibility, and a GTK+-based graphical user interface.
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Pencil is a standalone app that lets you create diagrams or UI mockups. It doesn't have collaboration/multi-user features.
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Lucidchart is a cloud-based platform that promotes teamwork through diagramming, collaboration, and data visualization. It serves millions worldwide, offering flowcharts, UML, real-time collaboration, Visio support, and browser access. Designed for innovation and understanding, it integrates easily into workflows.
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Google Drawings, part of Google Drive, allows users to collaborate creating, sharing, and editing images or drawings. It can be used for creating charts, diagrams, designs, flow-charts, etc.
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VYM (View Your Mind) is a tool to generate and manipulate maps which show your thoughts. Such maps can help you to improve your creativity and effectivity. You can use them for time management, to organize tasks, to get an overview over complex contexts, to sort your ideas etc.
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Feature-rich, open-source Wireflow offers a collaborative platform for online creation of complex user flow prototypes. Ideal for team work in UI design, wireframing, and mind mapping, promoting idea sharing in real-time environment aided by modern whiteboard features.
Web-based diagram platform offers real-time teamwork, 50+ diagram and mind mapping types, technical wireframing, smart objects, templates, version control, secure cloud storage, PDF export, collaboration tools, commenting, and integration for business and education use.
Australia
Design flowcharts, UML, Venn, and mind map diagrams with customizable templates, varied symbols, shapes, connector styles, overlapping sheet support, and intuitive drag-and-drop editing. Export visuals as images, edit multiple diagrams, and organize complex data visibly.
Australia
ProcessMaker is a cost effective and easy to use open source business process management (BPM) or workflow software application.
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