h2x is an engineering design and calculation platform developed for mechanical, plumbing, HVAC, and fire protection professionals. The software enables users to design building services systems while automatically calculating pipe sizes, duct dimensions, flow rates, velocities, and pressure losses. Its HVAC design tools support heating and cooling load calculations, ductwork layouts, hydronic systems, and equipment sizing. Plumbing capabilities include domestic water distribution, wastewater drainage, stormwater systems, and gas pipework design. Fire protection design features support sprinkler, hydrant, and hose system layouts and hydraulic sizing calculations. The platform connects engineering calculations directly to system drawings, allowing design changes to trigger automatic recalculation of affected components. Users can review systems in a 3D environment to identify potential coordination issues and evaluate system performance. h2x generates technical reports, branded PDF drawings, bills of materials, and files compatible with AutoCAD and Autodesk Revit. Its integrated workflow helps engineering consultants, contractors, and building services designers manage system calculations, technical documentation, and design coordination.