Next Generation Cool Calc Manual J is Finally Here

The long anticipated update to our revolutionary load calculation software is now available.


Create a Free Account today to get started

There is no cost to create a Cool Calc account. If you require ACCA approved Manual J Version 8 reports we offer convenient download packs for any budget.

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What's New in Cool Calc 3.0?

The latest version of Cool Calc Manual J is all about simplicity. We consolidated several screens and improved the map tracing capabilities. Users are now guided through the process from start to finish so even users with little experience can sucessfully complete a load calculation.

Now you can determine a home's heating and cooling requirements in minutes right from your mobile device with zero up-front costs. Create a free account and start using our redesigned tool today!

Awesome New Features

Cool Calc is the most advanced load calculation software available. Check out the new features included in our latest software release.

Lightning Fast

Version 3.0 is built for speed. Performance will no longer be compromised as we scale.


Improved Tracing

Our Google Maps tracing library for existing homes has been completely redesigned.


Full API

We now have a full API and SDK. Seamlessly integrate Cool Calc into an existing website or application.


Connector Exchange

Extend functionality with third-party plugins like Google Maps and the LennoxPros proposal tool.


Mobile-First Design

Our user interface now works flawlessly on mobile devices. It works on all other devices as well.


Enhanced Reports

In addition to our summary reports, detailed load calculation reports are now available.


How it works

Full API Available

Now manufacturers, distributors, or other software solutions can integrate Cool Calc directly into their website or application with a few lines of code. Click here to view our API documentation and obtain development credentials.

Full Privacy

Your customer info remains private. We never see user names, email, or any other identifiable information.


Turn-Key SDK

We provide API clients a full working software development kit (SDK) with a complete framework to customize your style.


Seemless Sign On

Automatically allow your users to access Cool Calc without needing to create a separate account.


Invite Team Members to Join Your Account

Have a large company? Our latest version allows you to invite unlimited team members to join your account.


Report Pooling

Purchase reports in bulk and share them across your entire team for greater savings.


Project Sharing

You can decide if team members can see each other's projects or only their own.


No Licensing Fees

Unlike other programs that charge per user, we don't charge extra for team members.

Mobile-First Design

Version 3.0 has been redesigned with a "mobile-first" approach. It is now easier than ever to perform a load calculation right from your mobile device.


Projects Created




Happy Clients



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User Feedback


Your tool saves me so much time. I can prep a load calculation before I get to a job site and then tweak it while on site directly from my phone or tablet. Keep up the good work.

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Thank you so much for developing this tool. I use it my classroom to teach students how to perform a proper load calculation. I love the fact that it is free and I don't have to invest in expensive software.

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Account Options

There is no up front cost or monthly subscription fees for a standard Cool Calc account and we don't ask for a credit card to register. Once you create an account you will be able to perform unlimited load calculations and view a summary of their results for free. If you later need to print or download an official ACCA Manual J report you can purchase one of our report download packs.

Standard Account

  • Unlimited view-only reports
  • Pay only for ACCA reports



API Account

  • Custom brand tool
  • Integrate with existing applications



ACCA Report Pricing

Report credits are only needed if you would like to download an official ACCA approved report (1 credit = 1 report). Report credits never expire and you can make unlimited changes to a system and re-generate reports without consuming additional credits. Click here to view a sample report.

Personal Pack

  • 5 ACCA Approved Reports



Team Pack

  • 30 ACCA Approved Reports


33% Discount

Enterprise Pack

  • 100 200 ACCA Approved Reports


Limited time discount!

Volume pricing

  • +500 ACCA Approved Reports

Custom pricing available if you expect to use more than 500 MJ8 report credits per year.

Frequently Asked Question

Below you will find some frequently asked questions on our software. For a full list of questions please visit our support site.

Creating your account on CoolCalc is totally free. With your free CoolCalc account you can do any number of load calculations and design the perfect HVAC system for your clients. If you require ACCA approved Manual J Version 8 reports we offer convenient download packs for any budget

Endless Integration

Cool Calc is designed in a way that it can pull home information and dimensional data from virtually any source. If you have a cool API that you would like to see integrated, reach out to us today.


Connector Exchange

Extend the functionality of Cool Calc with our Connector Exchange. Find third-party apps that integrate with our software

Google Maps

Google Maps


Use Google Maps to trace existing homes in seconds. Perfect for block-load calculations. Instantly obtain wall, ceiling, and floor areas as well as exposures.

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Lennox dealers can access Cool Calc for free through their LennoxPros login. Reports can also be tied to a projects generated through the Lennox proposal builder.

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Additional Connectors

Custom Connectors

Contact us

Do you have an application that would would like to connect with Cool Calc? Contact us today for information on our API and import schema.

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Subscribe to Stay Update

Join our mailing list and stay apprised of the latest feature updates. We also occasionally send discount offers on report packs.

Get In Touch

Have a question on our software? Feel free to reach out to us.

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    Malden, Massachusetts

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    (+1) 781-905-1010

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