Geometric design and strength check of spur gear with straight and helical toothing. Application is developed in MS Excel, is multi-language and supports Imperial and Metric units. Is based on ANSI/AGMA and ISO/DIN standards and support many 2D and 3D CAD systems (AutoCAD, AutoCAD LT, IntelliCAD, Ashlar Graphite, TurboCAD, Autodesk Inventor, SolidWorks, SolidEdge, Pro/E).