Hands Down Software

What Hands Down Software does

Hands Down Software is a privately held HVAC engineering software company founded in 1987 in San Rafael, California, that develops and sells psychrometric analysis and process charting software used by HVAC mechanical engineers, data center operators, building owners, and HVAC manufacturers. Its flagship product, HDPsyChart, is positioned as the world's #1 interactive psychrometric chart software and is used by over 20,000 engineers globally; supporting products include Akton Psychrometric Suite for industrial high/low-temperature applications, QwickLoad for HVAC load calculations, AcousticCalc for noise prediction, HDBinWeather for weather bin data, HDMakeUpAir for outside air energy analysis, and over a dozen additional desktop utilities. The technical foundation is a proprietary calculation engine, chart-rendering layer, and aggregated standards datasets — including ASHRAE 2015/2021 thermal guidelines, Standards 55 and 62.1, TMY2/TMY3, IWEC, and CWEC climatic data covering 9,100+ cities — exposed both as desktop applications and as DLL libraries for OEM embedding.

The company operates a multi-channel revenue model combining one-time perpetual licenses ($399 for HDPsyChart Pro V9; $499 for Akton), yearly subscriptions ($199 standard, $899 Deluxe with 20+ bundled engineering tools), royalty-free OEM/white-label licensing (deployed by 400+ companies including Carrier, Trane, Johnson Controls, Daikin, and ASHRAE), developer DLL licensing ($499-$4,999), and ancillary physical products (laminated charts, tear-off notepads). Go-to-market is direct-to-customer via the company website with online ordering, supplemented by a self-service subscription portal for enterprises with 10+ licenses. Hands Down Software was acquired by Carmel Software Corporation in Spring 2024; the combined entity now offers cross-platform mobile, web, IoT, and gbXML-integrated BIM capabilities under shared ownership at the same San Rafael, CA headquarters.

Name

Hands Down Software

Legal name

Hands Down Software Corporation

Website

https://handsdownsoftware.com

Company type

Private

Founded year

1987

Operating status

Operating

Headcount range

1–10 employees

Short description

Hands Down Software develops psychrometric analysis and HVAC design software, including the HDPsyChart platform used by 20,000+ engineers and white-labeled by 400+ HVAC manufacturers worldwide. Founded in 1987 and acquired by Carmel Software in 2024.

Ownership category

akta.pro rank

Product category

HVAC Engineering Software

NAICS

Software Publishers (5132), Custom Computer Programming Services (541511)

SIC

Services-Prepackaged Software (7372), Services-Computer Programming Services (7371)

akta.pro primary industry

HVAC/R Controls, Automation & Smart Thermostats (EDAOACAE)

Keywords

• Psychrometric analysis software
• HVAC engineering software
• Psychrometric chart software
• HVAC load calculations
• Psychrometric DLL libraries

Headquarters

HQ city

Oklahoma City

HQ country

United States

HQ region

North America

Offices1 record

Markets served

GTM type

B2B

Offering type

Software

Cost components

Personnel, Technology or R&D, Operations, Marketing or Sales, Infrastructure

Revenue model

1. Software License Sales (Perpetual): One-time perpetual license fee for HDPsyChart V9 at $399 per license. Customers can use the software in perpetuity but receive no updates beyond minor bug fixes.
2. Subscription Licensing: Yearly subscription service at $199/license providing yearly updates, unlimited support via phone/email, yearly training sessions (min 10 licenses), access to online licensing portal (min 10 licenses), and logo customization (min 10 licenses).
3. Deluxe Subscription: Premium subscription at $899/year including all standard subscription benefits plus 20 additional engineering software tools, more frequent ASHRAE/TMY3 data updates, individual training, and premium same-hour support.
4. DLL Component Licensing: Software libraries sold to developers for integration into custom applications. HDPsyChart DLL priced at $4,999 (no royalty), HDMakeUpAir DLL at $3,999 (no royalty), AcousticCalc DLL at $999, with various other DLLs ranging from $499 to $2,999.
5. OEM/White-label Licensing: Over 400 companies worldwide have white-labeled HDPsyChart with custom logos and color schemes. OEM version pricing starts at $399 for customized branded versions.
6. Physical Products: Sale of laminated psychrometric charts (11x17 inches, minimum 25 units at $20 each) and tear-off notepads (8.5x11 inches, minimum 20 pads at $11 each).

Pricing tiers

Go-to-market motion1 record

Distribution channels4 records

Marketing channels4 records

Core offering

Hands Down Software develops and sells HVAC engineering software centered on psychrometric analysis, with its flagship HDPsyChart V9 being the leading interactive psychrometric chart application used by 20,000+ engineers worldwide. The portfolio also includes industrial psychrometric tools (Akton), HVAC load calculators (QwickLoad), noise prediction (AcousticCalc), outside air energy analysis (HDMakeUpAir), weather bin data tools (HDBinWeather), and a suite of DLL developer libraries licensed to OEMs and software integrators.

Product overview

Hands Down Software offers a comprehensive portfolio of HVAC engineering software tools centered around psychrometric analysis. The core product is HDPsyChart Version 9, the world's #1 psychrometric chart software used by 20,000+ engineers, available in Professional ($399 perpetual or $199/year subscription), Standard, and OEM white-label versions. Supporting products include Akton Psychrometric Suite V9 for industrial high/low temperature applications ($499), QwickLoad for residential/commercial HVAC load calculations ($199-$599), AcousticCalc for noise prediction ($499), HDMakeUpAir for outside air energy analysis ($299), HDBinWeather V9 for weather bin data ($299), and additional tools like HDPsyTech calculator, HDClimatic weather data (9,100+ cities), HDFreshAir ventilation calculator, HDAcoustic plenum analysis, HDConvert unit conversion, HDComfort thermal comfort (ASHRAE 55/ISO 7730), HDDuctDesign, HDEvapCool, and HDElectHeat. Physical products include laminated 11"x17" psychrometric charts and 8.5"x11" tear-off notepads. Developer tools are offered as DLLs (HDPsyChart $4,999, HDMakeUpAir $3,999, AcousticCalc $999, HDBinWeather $2,999) and ActiveX components for OEM integration. Carmel Software (parent company acquired in Spring 2024) also provides custom software development services including mobile apps for iOS/Android, web-based equipment selection software, HVAC IoT development, and gbXML support. Over 400 companies have white-labeled HDPsyChart OEM versions.

Differentiator

Problem solved

Functional benefit

Products and services

• HDPsyChart Professional Version 9 World's #1 interactive psychrometric chart software for HVAC engineers; complete psychrometric and process analysis with ASHRAE data zones, comfort zones, weather data plotting, state point and process reports; supports IP and SI units and 20 languages. Sold as perpetual ($399), annual subscription ($199/yr), or Deluxe subscription ($899/yr).
• Akton Psychrometric Suite Version 9 Industrial psychrometric software for very high and low temperature/pressure ranges (-100 to +2,000 °F, humidity ratios up to 1 lb/lb, altitudes up to 45,000 ft or pressures up to 100 psia). Designed for agricultural storage, food processing, power generation, chemical manufacturing, and petroleum refining.
• QwickLoad Commercial and residential HVAC load calculation software. Available in residential (up to 10 zones), commercial (up to 500 zones), and combo-pack versions, sold through Hands Down Software as bundle options.
• AcousticCalc HVAC noise prediction and acoustical analysis software for comprehensive sound power level estimation in air handling units and plenums. Standalone product with DLL version available.
• HDMakeUpAir Outside air energy estimation software providing detailed and precise outside air energy estimations for thousands of worldwide locations, with support for energy efficiency, COP, utility costs, and energy recovery device evaluation.
• HDBinWeather V9 Weather bin data table creation software with 2023 U.S. TMY3 data from Climate.OneBuilding.org (8760 hourly data for 2,700 U.S. cities), TMY2, IWEC, CWEC, and worldwide weather data from multiple international sources.
• HDPsyTech Simple desktop psychrometric property calculator that accepts any properties as input and calculates remaining psychrometric properties. Supports both IP and SI units.
• HDClimatic Outside air design conditions for over 9,100 domestic and international locations, based on ASHRAE 2021 Fundamentals Handbook, providing winter heating, summer cooling, and wind data.
• HDFreshAir Fresh air estimates based on ASHRAE Standard 62.1-2004 for determining approximate outside air volumes for proper indoor air quality.
• HDAcoustic Plenum sound analysis tool that accepts source sound power levels in standard octave bands and estimates sound power levels at openings based on housing plenum geometries and construction.
• HDConvert IP to SI units conversion tool covering length, area, volume, pressure, velocity, flow rates, weights, concentrations, energy, power, angles, and rotation speed.
• HDComfort Thermal comfort calculator predicting human thermal response using PMV-PPD and ET*-DISC models, referencing ASHRAE Standard 55 and ISO Standard 7730.
• HDDuctDesign Duct design calculator for quick and accurate duct size and/or pressure drop calculations. Supports round, rectangular, and oval ducts with standard air or actual air corrections.
• HDEvapCool Evaporative cooler performance calculator that properly corrects for altitude and allows specification of cooler size/effectiveness.
• HDElectHeat Electric heater performance calculator that properly corrects for altitude and checks design for safety parameters such as watt density.
• CleanCalc Cleanroom and lab energy simulation analysis program for specialized HVAC applications in laboratory and cleanroom environments.
• HDPsyChart OEM (White-Label) Version Customized version of HDPsyChart with company logo and color scheme, priced at $499. Over 400 companies worldwide have white-labeled the software, including ASHRAE, Trane, Carrier, York, Lennox, Johnson Controls, Daikin, and AAON.
• HDPsyChart DLL Dynamic link library for software developers to pass project information, state points, and processes to the psychrometric chart engine for display. No royalty fee, priced at $4,999.
• HDMakeUpAir DLL Component engine DLL for software developers needing to estimate outside air loads and energy needed to heat, cool, humidify, and de-humidify outside air. No royalty fee, priced at $3,999.
• HDBinWeather DLL DLL providing access to complete hourly weather data from TMY3, IWEC, and CWEC files with customized bin weather data capabilities. No royalty fee, priced at $2,999.
• HDAcoustic DLL / AcousticCalc DLL DLL enabling software developers to estimate sound power levels for air handling units or plenums with custom coefficients support. No royalty fee, priced at $999.
• HDClimatic DLL Dynamic link library providing outside air design conditions for over 1,459 cities worldwide based on ASHRAE's 1997 Fundamentals Handbook.
• HDConvert DLL IP to SI unit conversion library for developers, covering length, area, volume, pressure, velocity, flow rates, weights, concentrations, energy, power, angles, and rotation speed.
• HDComfort DLL Thermal comfort DLL using PMV-PPD and ET*-DISC models referencing ASHRAE Standard 55 and ISO Standard 7730.
• HDDuctDesign DLL Duct calculation library for developers needing quick and accurate duct size and/or pressure drops for round, rectangular, and oval ducts. No royalty fee.
• HDFreshAir DLL Fresh air calculation DLL based on ASHRAE Standard 62.1-2004 Table 6.1 for determining outside airflow estimates.
• HDEvapCool DLL Evaporative cooling DLL allowing software developers to pass cooler size or efficiency and receive complete performance output.
• HDElectHeat DLL Electric heating DLL for software developers needing to calculate electric heater performance with air temperature rise or kW input.
• HDPsyTech DLL 64-bit psychrometric calculator DLL written in Visual Studio .NET for developers needing psychrometric properties for standard and extreme conditions.
• HVAC Equipment Selection Software Custom desktop and web-based HVAC equipment selection software development service. Carmel Software has developed custom equipment selection software for over 50 HVAC manufacturers including Carrier, Mitsubishi Electric, Honeywell Phoenix Controls, and others using its ESS Physics Engine template.
• Custom Software Development Custom software development services for Microsoft Windows, web, mobile (iPhone/Android), and tablet platforms, including psychrometric chart software, equipment selection, HVAC IoT software, and building system energy analysis.
• HVAC Internet of Things (IoT) Development IoT software development for HVAC companies, including mobile apps communicating with Bluetooth-enabled HVAC metering and measurement devices. Past clients include Uniweld Products (refrigerant charge calculations with BLE), Inficon (refrigerant tank scale communication), Beckett Corporation (boiler diagnostics), and Energy Conservatory (blower door testing).
• gbXML Support Services Green Building XML schema support services. Carmel Software is a member of the gbXML.org Board of Directors and has developed mobile and web-based software tools that support gbXML for BIM to engineering analysis tool data transfer.
• Laminated Psychrometric Charts 11"x17" laminated psychrometric charts created from HDPsyChart V9 and Akton Psychrometric Chart, available in full color with heavy laminate on front and back. Minimum order of 25 charts at $20 each.
• Tear-Off Notepads 8.5"x11" psychrometric chart tear-off notepads on 70 lb uncoated paper, front-printed only, with cardboard back. Minimum order of 20 pads (25 sheets each) at $11 per pad.

Quantifiable outcome

• 20,000+ engineers worldwide rely on HDPsyChart for HVAC design
• +3 more outcomes

Named customers14 records

Segments6 records

Ideal customer profiles5 records

Technology focussed Yes

API detail

Has API

No

API docs

API detail

Core technology

AI maturity

App detail

Integration5 records

Feature6 records

Partnerships

Eleven partnerships are on record, tiered core and major.

• Carmel SoftwarecoreStrategic or Co-development Partner · 1 April 2024In Spring 2024, Carmel Software acquired Hands Down Software along with the psychrometric chart software and other software tools. Carmel Software is a leader in mobile and web-based HVAC software since 1995. Plans include continuing to support 20,000+ HDS users while updating the software with new releases.
• ASHRAEcoreStrategic or Co-development PartnerASHRAE is a major customer and standards organization partner. Carmel Software has developed custom mobile apps for ASHRAE standards, web-based tools for ASHRAE Standard 140 and 90.1 compliance, and participates in ASHRAE research projects including RP-1815 for occupant behavior data integration with BIM.
• AutodeskcoreStrategic or Co-development PartnerIn 2010, Autodesk acquired Carmel Software's desktop HVAC software assets including Design-Build, Duct Size, Estimate, Loadsoft, Refrigeration, Residential, and Green Toolbox products. Carmel source code was integrated into Autodesk Revit MEP for building thermal analysis.
• Johnson ControlsmajorStrategic or Co-development PartnerCarmel Software developed a web-based JavaScript HVAC psychrometric calculator for Johnson Controls to aid in selection of their residential HVAC equipment line.
• Mitsubishi ElectricmajorStrategic or Co-development PartnerDeveloped 'Diamond System Builder' - a comprehensive VRF equipment selection software tool for Mitsubishi Electric's entire line of HVAC equipment, allowing users to layout indoor/outdoor units, export to Excel and AutoCAD, and perform complex performance calculations.
• Honeywell (Phoenix Controls)majorStrategic or Co-development PartnerCo-developed PC Optimizer - a comprehensive HVAC system energy analysis software tool for Honeywell's Phoenix Controls division, used by salespeople and customers to calculate energy savings of Phoenix Controls valves versus conventional HVAC valves.
• SMACNAmajorStrategic or Co-development PartnerAwarded 2 software development contracts in 2022 to develop a web-based HVAC ductulator application and graphical HVAC exhaust design software tool for the Sheet Metal and Air Conditioning Contractors' National Association.
• IBPSA-USAmajorStrategic or Co-development PartnerAwarded software development contract in Fall 2023 to develop a web-based software portal for ASHRAE Standard 140 compliance and validation. Follow-on contract awarded in Fall 2024 to update for ASHRAE Standard 90.1-2019 PRM and ECB methods.
• Society of Fire Protection Engineers FoundationmajorStrategic or Co-development PartnerCompleted research project in 2024 to study integration of fire protection systems with BIM. Deliverable was March 2024 final report on software and workflows.
• U.S. Department of EnergymajorStrategic or Co-development PartnerWon 2020 DOE grant to develop Schema Server - a web-based tool to help DOE and private-company software tools share building energy auditing information. Additional projects include building energy analysis tools.
• gbXMLcoreTechnology or IntegrationCarmel Software is a member of the Board of Directors of gbXML.org which houses the Green Building XML open schema. The schema facilitates transfer of building properties from BIM tools to engineering analysis tools. gbXML has industry support from Autodesk, Bentley, Trane, DOE, and NREL.

Scale indicators6 records

Recent moves6 records

Expansion highlights5 records

Broad incumbents

• IES (Integrated Environmental Solutions): IES Virtual Environment (VE) is a comprehensive building performance analysis suite that includes thermal, energy, daylighting, and psychrometric analysis capabilities used by mechanical engineers, overlapping with Hands Down's core psychrometric and HVAC design value proposition.
• Bentley Systems (Hevacomp): Bentley's Hevacomp is a commercial HVAC design and analysis tool used by mechanical engineers in the same psychrometric and load calculation workflows as HDPsyChart, part of Bentley's broader building design portfolio including OpenBuildings and AECOsim.
• Trane Technologies (TRACE): Trane's TRACE 700 and TRACE 3D Plus are direct competitors in HVAC load and energy analysis, used by mechanical engineers for similar psychrometric and system design workflows. Trane is also a Hands Down Software white-label customer.
• Autodesk (Revit MEP): Autodesk's Revit MEP incorporates psychrometric analysis functionality originally developed by Carmel Software (Hands Down's parent, acquired by Autodesk in 2010), bundling psychrometric capabilities into BIM/3D building design workflows used by the same engineering audience.
• Carrier (HAP): Carrier's Hourly Analysis Program (HAP) is a leading commercial HVAC load and energy analysis tool that competes with HDPsyChart's psychrometric and load calculation functionality, though bundled into Carrier's broader equipment ecosystem. Carrier is also a Hands Down Software white-label customer.

Direct peers

• Elite Software: Elite Software develops HVAC load calculation and duct design software (CHVAC, VisualDuct, VisualPipe) used by mechanical engineers for the same psychrometric, load, and duct workflows as HDPsyChart and QwickLoad. Closest direct peer among independent HVAC design software vendors.
• Mitsubishi Electric (Diamond System Builder): Mitsubishi Electric's Diamond System Builder is a VRF equipment selection tool originally developed by Carmel Software (Hands Down's parent), making it both a product peer in HVAC selection software and a strategic partner. Targets similar HVAC engineering workflows.

Emerging players

• DesignBuilder: DesignBuilder provides EnergyPlus-based building performance simulation software for HVAC engineers, with psychrometric and thermal analysis capabilities. A more specialized alternative to full-suite incumbents, competing for the same mechanical engineering audience at a lower price point.

Others

• EnergyPlus: EnergyPlus is the U.S. DOE's open-source whole-building energy simulation program that performs detailed psychrometric and HVAC calculations, often used as the underlying engine for tools like DesignBuilder and IBPSA-USA validators. Represents the open-source competitive alternative in the same engineering workflow.
• Honeywell (Phoenix Controls): Honeywell's Phoenix Controls division partnered with Carmel Software (Hands Down's parent) to co-develop PC Optimizer, a custom HVAC energy analysis tool. While primarily a controls manufacturer, the partnership positions Honeywell as a related player in HVAC analysis software for the same customer base.

Market position

Strengths4 records

Weaknesses4 records

Competitive moat5 records

Key risks5 records

Key highlights6 records

Customer concentration

• Xx.com/handsdownsoft
• LinkedInlinkedin.com/company/hands-down-software

Revenue estimate

Valuation estimate

Number of profiles

Funding overview

Funding rounds

Investors

Funding detail is available on the Subscription and Enterprise plan.Contact sales →

M&A

Investments

M&A and investment is available on the Subscription and Enterprise plan.Contact sales →

Frequently asked questions about Hands Down Software