Top 9 Free and Open-Source Diagramming Tools

With the advent of software development and software industry advancement, the need for documenting procedures, specifications, user manuals, etc., has drastically increased. Every company is seeking a technical writer that can meet these documentation requirements which overall ensures and proves an organization's professional standing. In almost every document, a diagram is required. In fact, in most of the software documentation, different diagrams, such as use case diagrams, flow charts, data flow diagrams, etc., are required and without which the document is not accepted. Therefore, there exists a list of diagramming tools that allow the technical writers and software engineers to draw different UML diagrams along with providing the open-source functionality enabling and providing grounds for more feature enhancements.

Here at Ibmi Media, as part of our Server Management Services, we regularly help our Customers to perform related Open Source Software reviews.

In this context, we shall look into the best Open Source diagramming tools.

1. Diagrams.net

Diagrams.net, formerly known as draw.io, is a diagramming tool that comes equipped with shapes and tools to draw any kind of diagram. The software, mechanical, electrical engineers can get benefitted from the simple and most intuitive tool that allows support for every diagram. Diagrams.net is adapted by many platforms such as Atlassian Confluence and Jira, WikiSuite.org, etc. The diagramming tool seamlessly synchronizes with popular software like Google Workplace, Google Drive, Microsoft OneDrive, SharePoint, Dropbox, NextCloud, GitHub, and more. The tool integrates and fetches data from a well-defined CSV or an excel file. Also, the tool can be integrated with Atom, BookStack, Docstell, etc. Other diagramming features include quick shape rotation, add and text wrapping ability in the shapes, shape connectors, enhanced and most advanced shapes library with the ability to search any shape in the provided search box, free access to Amazon architecture diagram, etc. The tool can be downloaded or can be used online.

Get it now from http://get.diagrams.net/

2. Dia

Released in 1998, the advanced and feature-packed diagramming tool offers numerous tools that enhance user experience. The free and open-source Dia Diagram Editor is a platform that is also cross-platform compatible, i.e., the tool offers a seamless user experience to Linux, macOS, and Windows users. With Dia, users can create a list of different diagrams. Other features of the platform include an Org Chart tool allowing creating organizational charts, Character Separated Files (CSV) compatibility, enhanced diagram layouts, graphics, shapes, data import and export capabilities, ability to utilize predefined objects and symbols, users are able to export diagrams in a list of formats such as PNG, SVG, WMG, XFIG, etc. and the list of features and functionalities goes on.

Get it now from https://sourceforge.net/projects/dia-installer/files/dia-win32-installer/0.97.2/dia-setup-0.97.2-2-unsigned.exe/download

3. Calligra Flow

Developed by the free and open-source software solutions developers, KDE (K(ool) Desktop Environment), Calligra Flow is one of the highly appraised and adopted platforms for diagramming and creating intuitive illustrations. Calligra Flow offers a user interface that is quite similar to the Microsoft Vision and hence is quite adopted by Visio users and even for beginners. The tool offers many advanced features such as the capability to draw flowcharts, different diagrams, organizational charts, etc., extensive support and compatibility with Dia stencils, vector drawing features, integrated components, visual database application integration, ability to create presentations, create and design mathematical calculations utilizing spreadsheet, python developers can create customized stencils, etc.

Get it now from https://calligra.org/download/

4. LibreOffice Draw

LibreOffice Draw is part of the LibreOffice Suite and therefore anyone with their hands on the other products of the LibreOffice, can easily get themselves acquainted with the LibreOffice Draw tool. Like its other products, LibreOffice draw is free and open-source as well. The tool offers an intuitive platform to draw any diagram and offers a list of features to its users. These features mainly include predefined flowchart and other diagramming shapes, an extensive help facility that is accessed from the Help menu, diagram connection points, multiple pages, text wraps feature that wraps text within a shape, spell-check, ability to import, export, and edit PDFs, import Microsoft Visio .vsd files, Microsoft Publisher .pub files, etc.

Get it now from https://www.libreoffice.org/download/download/

5. Apache OpenOffice Draw

Launched in 2012 by the software solutions development giants – Apache Software Foundation, the Apache OpenOffice is a free and open-source office suite that incorporates several tools enabling simple, adaptable, and economical data creation and management capabilities. Apache OpenOffice is cross-platform compatible and offers a seamless user experience for Linux, macOS, Microsoft Windows users across the globe. The Drawing tool that comes equipped in the office suite is capable of responding to all the user’s diagramming needs. The key features offered in the intuitive Apache OpenOffice Draw tool are quite similar to the features offered by the LibreOffice Draw. With the tool, users are able to create different organizational diagrams, flowcharts, network diagrams, etc.

Get it now from https://www.openoffice.org/download/index.html

6. Inkscape

Inkscape was developed in 2003 and is a free and open-source diagramming and photo-editing software. Inkscape is a cross-platform compatible tool that can be used by Linux, macOS, Windows, and FreeBSD users. Despite offering a list of intuitive and most attractive diagramming capabilities, users can also get their hands on the vast list of photo editing features as well, these features mainly include vector graphics tool is feature-packed with a list of tools required to edit ellipses, rectangles, polygons, arcs, stars, spirals, and 3D boxes, etc. The diagramming features offered in the platform include object creation and manipulation, text operations, fills and stroke rendering, utilization, and compatibility with the W3C open standard SVG (Scalable Vector Graphics) format, export and import functionalities supporting several file formats, such as SVG, PDF, PS, PNG, AI, EPS, etc.

Get it now from https://inkscape.org/release/inkscape-1.1/


7. Diagramo

Diagramo is yet another feature-packed diagramming tool that is both free and open-source. The software comes under the GPL license and offers a list of advanced diagramming tools and functionalities. With Diagramo, the users are even able to communicate and collaborate on the projects or diagrams. The users can readily access the efficient diagramming tool from the web and use the platform online. The software can also be used locally by downloading on the PHP-based servers. Users can export the diagrams created on the platform in PNG, JPEG, SVG, and GIF formats. The platform also allows users to share the diagrams directly from the system with the user’s team members etc.

Start using it now from http://diagramo.com/editor/editor.php

8. Pencil

Pencil is another very intuitive and highly adopted diagramming tool that offers a list of vast functionalities. The pencil diagramming tool is free, open-source, and offers compatibility with all the leading operating systems. The features offered in the platform include a range of shapes that users can use to design different desktop and mobile user interfaces, pre-installed stencils for iOS and Android platforms, flowchart elements, general-purpose shapes, shape connectors, ability to export documents to numerous formats such as, PDG, SVG, and also LibreOffice, etc., ability to search a particular shape or clipart directly from the internet through the pencil platform, and the list of enhanced features and capabilities goes on.

Get it now from https://pencil.evolus.vn/Downloads.html

9. Lucidchart

If you are looking for a powerful diagramming tool, then Lucidchart will serve your purpose. This is free diagram software solution  for a single user. It will allow the user to visualize processes and models.

The software allows multiple users to share the documents and work on them simultaneously and effortlessly. The whole team can think visually and helps in increasing productivity. 

Drawing flowcharts, org charts, UML, mind maps, and wireframes are much easier with this software. The intuitive system of this tool will help users in the field of web designing, web development, and engineering. You will find this system reliable and easy-to-use.

Get it now from https://www.lucidchart.com/

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This article covers the best free and open-source diagramming tools that are widely adopted and adapted by individuals, companies, enterprises, and different institutes such as Diagrams.net, Dia, Calligra Flow, LibreOffice Draw, Apache OpenOffice Draw, Inkscape, Diagramo, and Pencil. 

The diagram app is quite helpful and valuable. You can build and visually shape your ideas to the audience by employing intuitive diagramming tools. The users can make beautiful diagrams from scratch with the help of diagram software technique.