The calculation is intended for the purposes of geometric and strength designs of helical compression cylindrical springs made of wires and rods of circular sections, loaded with static or fatigue loading. Application is developed in MS Excel, is multi-language, supports Imperial and Metric units and solves the following main tasks: - Automatic design of a spring. - Selection of an optimal alternative of spring design in view of strength, geometry and weight. - Static and dynamic strength check. - Support for Cold formed springs and Hot formed springs - Calculation of working forces of a spring of known production and installation dimensions. - Calculation of installation dimensions for known loading and production parameters of the spring. - The application includes a table of commonly used spring materials according to ISO, ASTM/SAE, DIN, BS, JIS and others. - Support of 2D CAD (AutoCAD, AutoCAD LT, IntelliCAD, Ashlar Graphite, TurboCAD) and 3D CAD in full calculation package (Autodesk Inventor, SolidWorks). The calculation is based on data, procedures, algorithms and data from specialized literature and standards EN 13906-1, DIN 2089-1, DIN 2095, DIN 2096.This module is a part of MITCalc - Mechanical and Technical Calculation Package for gear, belt and chain drives, springs, beam, shaft, bolt connection, shaft connection, tolerances and many others.