Free Engineering Tools
Professional HVAC and plumbing calculation tools - no login required
Duct Sizer
Size round, rectangular, and oval ducts using ASHRAE equal friction or velocity methods
HVACPipe Sizer
Size piping using Hazen-Williams or Darcy-Weisbach methods with velocity and pressure drop
PlumbingPsychrometric Chart
Interactive ASHRAE psychrometric chart with process calculations for HVAC design
HVACUnit Converter
Convert between IP and SI units for temperature, flow, pressure, and more
GeneralVentilation CFM
Calculate outdoor air requirements per ASHRAE 62.1 ventilation rate procedure
HVACQuick Load Estimator
Estimate cooling and heating loads using SF/ton and BTU/SF rules of thumb
HVACFixture Units
Calculate water supply and drainage fixture units per IPC 2024
PlumbingKitchen Exhaust
Calculate exhaust hood CFM per IMC and ASHRAE 154 for commercial kitchens
HVACSprinkler Hydraulics
Calculate sprinkler system demand per NFPA 13 for fire protection design
FireGas Pipe Sizer
Size natural gas and propane piping per NFPA 54 and IFC
PlumbingGrease Interceptor
Size grease interceptors per IPC and PDI G-101 for food service
PlumbingProfessional Calculations, Free for Everyone
These tools use the same ASHRAE-based calculation methods as the full J∆S Engineering Suite desktop application. They're perfect for quick calculations, preliminary design, and field estimates.
ASHRAE Compliant
All calculations follow ASHRAE Fundamentals methodology
No Login Required
Use these tools instantly without creating an account
Engineer Developed
Built by MEP engineers for real-world design work
Need More Power?
The full J∆S Engineering Suite includes comprehensive load calculations, energy simulation, code compliance checking, Revit/AutoCAD integration, and much more.