Top 10 Best Load Calculation Software of 2026

Wrightsoft Right-Suite Universal is a leading HVAC design software suite specializing in precise load calculations for residential and light commercial buildings, fully compliant with ACCA Manual J, D, and S standards. It enables detailed room-by-room and block load analysis, incorporating factors like infiltration, ventilation, psychrometrics, and building envelope details. The platform integrates load calculations with duct design, equipment selection, and 3D modeling via Right-Draw, streamlining the entire HVAC design workflow.

Carrier HAP (Hourly Analysis Program) is a professional-grade software suite designed for precise HVAC load calculations, annual energy analysis, and system sizing using ASHRAE-approved methods. It supports detailed modeling of buildings zone-by-zone, incorporating weather data, infiltration, ventilation, and extensive equipment libraries for accurate peak load and energy simulations. Widely used in commercial and institutional projects, HAP generates comprehensive reports for design validation and code compliance.

Trane TRACE 3D Plus is a comprehensive building energy modeling software designed for HVAC load calculations, whole-building energy simulations, and system optimization in commercial projects. It utilizes advanced 3D modeling tools to create detailed building geometries and performs hour-by-hour load calculations based on ASHRAE standards. The software also supports life-cycle cost analysis, LEED compliance, and integration with Trane's equipment selection libraries for seamless design workflows.

Elite RHVAC from Elite Software is a veteran Windows-based tool designed specifically for residential HVAC load calculations, fully compliant with ACCA Manual J (8th Edition) and supporting ASHRAE standards. It enables detailed input of building geometry, construction assemblies, insulation, infiltration, internal gains, and ventilation to compute precise heating and cooling loads on a zone-by-zone basis. The software produces professional-grade reports for equipment sizing, code compliance, and permitting, with options for integration into broader HVAC design workflows using other Elite products.

CoolCalc is a cloud-based HVAC load calculation software that performs accurate Manual J calculations for residential and light commercial buildings in compliance with ACCA standards. It features an intuitive wizard-driven interface that simplifies data entry for building geometry, insulation, and equipment selection. The platform generates detailed reports, equipment sizing recommendations, and supports integration with design tools, all accessible via web browser without installation.

EnergyGauge USA is a professional-grade software for residential HVAC load calculations, fully compliant with ACCA Manual J (8th Edition), providing precise heating and cooling load estimates. It supports detailed inputs for building envelopes, infiltration, internal gains, and duct design per Manual D, along with equipment selection via Manual S. The tool generates comprehensive reports accepted by building officials and includes features for whole-house and zone-by-zone analysis.

Loadsoft from Carmel Software is a Windows-based load calculation tool primarily used by HVAC professionals for accurate residential and light commercial heating and cooling load computations compliant with ACCA Manual J 8th Edition. It generates detailed reports including block load, room-by-room breakdowns, and equipment sizing recommendations. The software emphasizes precision and has been a reliable option for manual calculations without cloud dependencies.

EnergyPlus is a state-of-the-art, open-source whole-building energy simulation software developed by the U.S. Department of Energy, capable of modeling complex heating, cooling, lighting, and ventilation systems to predict hourly energy loads and consumption over time. While primarily designed for detailed dynamic energy modeling, it can perform load calculations through its transient simulation engine, integrating weather data, building geometry, and HVAC systems for accurate peak load estimates. It supports advanced features like custom control strategies and is widely used for energy code compliance and performance optimization.

eQUEST, available from energy-design-tools.com, is a free building energy simulation software based on the DOE-2.2 engine, capable of performing detailed heating and cooling load calculations as part of comprehensive whole-building energy modeling. It supports inputs for building geometry, internal loads, infiltration, HVAC systems, and weather data to generate accurate peak load estimates and hourly profiles. Primarily used for energy code compliance like Title 24 and ASHRAE 90.1, it excels in integrating load calcs with annual energy simulations for design optimization.

OpenStudio is an open-source software platform developed by NREL for whole-building energy modeling and simulation, providing a graphical user interface to EnergyPlus. It enables detailed load calculations as part of comprehensive energy analyses, including zone-by-zone heating and cooling loads, peak load identification, and integration with standards like ASHRAE 90.1. While powerful for advanced simulations, it is more suited to energy modeling than standalone, quick load calculations.