BRL-CAD!

SketchUp (formerly Google Sketchup) is a 3D modeling computer program for a wide range of drawing applications such as architectural, interior design, civil and mechanical engineering, film, and video game design—and available in a freeware version, SketchUp Make, and a paid version with additional functionality, SketchUp Pro.

FreeCAD is a general purpose parametric 3D CAD modeler. The development is completely Open Source (LGPL License). FreeCAD is aimed directly at mechanical engineering and product design but also fits in a wider range of uses around engineering, such as architecture or other engineering specialties.FreeCAD features tools similar to Catia, SolidWorks or Solid Edge, and therefore also falls into the category of MCAD, PLM, CAx and CAE. It is a feature based parametric modeler with a modular software architecture which makes it easy to provide additional functionality without modifying the core system.As with many modern 3D CAD modelers it has many 2D components in order to sketch 2D shapes or extract design details from the 3D model to create 2D production drawings, but direct 2D drawing (like AutoCAD LT) is not the focus, neither are animation or organic shapes (like Maya, 3ds Max, Blender or Cinema 4D), although, thanks to its wide adaptability, FreeCAD might become useful in a much broader area than its current focus.FreeCAD makes heavy use of all the great open-source libraries that exist out there in the field of Scientific Computing. Among them are OpenCascade, a powerful CAD kernel, Coin3D, an incarnation of Open Inventor, Qt, the world-famous UI framework, and Python, one of the best scripting languages available. FreeCAD itself can also be used as a library by other programs.FreeCAD is also fully multi-platform, and currently runs flawlessly on Windows and Linux/Unix and Mac OSX systems, with the exact same look and functionality on all platforms. »

AutoCAD is a software application for both 2D and 3D computer-aided design (CAD) and drafting — available since 1982 as a desktop application and since 2010 as a mobile web- and cloud-based app, currently marketed as Autocad 360.

OpenSCAD is a software for creating solid 3D CAD objects. It is free software and available for Linux/UNIX, MS Windows and MacOS.

DraftSight is a professional-grade, open 2D CAD product for users who want a better way to read, write and share DWG files. DraftSight is easy to use and is available for professional CAD users, students and educators to download and activate for free.*

A powerful CAD platform, with features familiar to you from native .dwg applications. BricsCAD® unifies advanced 2D design with the intelligence of 3D direct modeling. For Windows, Linux, and Mac.

DesignSpark Mechanical is a 3D modeling software reported to be easy to use so that all engineers will be able to create and share models.Designs can be linked directly to RS/Allied off-the-shelf components for automatic bill of materials generation, part numbers, and costs for included components.DesignSpark Mechanical can export to DXF, SketchUp, ECAD, OBJ, STEP, and STL formats. Since the software is free, designs can be shared in native electronic form for providing 3D models to your customers and sharing with other engineers and management involved with the project. Designs can be sent directly to rapid prototyping/3D printer devices for quick prototyping. »

Browser based 3D solid CAD editor, Openscad style, with a Coffeescript based syntax, using only Coffeescript + Javascript

Creo Elements/Pro – formerly Pro/ENGINEER – is the standard in 3D product design, featuring state-of-the-art productivity tools that promote best practices in design while ensuring compliance with your industry and company standards. Integrated, parametric, 3D CAD/CAM/CAE solutions allow you to design faster than ever, while maximizing innovation and quality to ultimately create exceptional products.

Antimony is a computer-aided design (CAD) tool from a parallel universe in which CAD software evolved from Lisp machines rather than drafting tables.

TurboCAD is a CAD software suite, with several different feature levels. It is a competitor to the likes of Autodesk's AutoCAD program, and is used by engineers, architects and hobbyists.

OpenJSCAD.org is a more up-to-date OpenJsCAD frontend where you can edit .jscad files either locally or online via JS editor (built-in). A few functions are available to make the transition from OpenSCAD to OpenJSCAD easier (OpenSCAD.jscad built-in), as well CLI (command-line interface) for server-side computations with NodeJS.

KOMPAS-3D is for creating three-dimensional associative models for individual parts and assembly's containing both original and standardized elements. The parametric technology allows quickly obtaining models for typical products basing on a once designed prototype. Numerous service functions facilitate solving auxiliary designing and production maintenance problems.

Want to focus your time and energy on developing designs to build a better world? MicroStation easily models, drafts, maps, renders and documents your projects.

progeCAD Smart 2009 is a limited version of progeCAD . It is free for private, non-commercial use only. You need to register the software to continue using it after 30 days. Of course registration is totally free.