CoolCalc review

CoolCalc is the easiest way on this list to get an ACCA-based load and duct design without installing anything. It runs in any modern browser on a Mac, PC, phone or tablet, and the project can be shared with others in your company or with an outside reviewer such as a HERS rater. Geometry can come from a floor plan upload, a satellite trace for quick block loads, manual drawing, or the CoolCalc Scan app, which uses the LiDAR scanner on an iPhone 12 Pro or newer or an iPad Pro to capture rooms on site. Manual S draws on an equipment database covering dozens of brands. Pricing is flexible: you can build a project for free, then pay $45 to see the results, or subscribe to Pro at $50 per user a month for unlimited reports and ticketed support. It does not handle commercial ASHRAE loads, and the proposal and CRM features sit on a Pro Plus plan the vendor listed as coming soon.

Who it is for

Contractors who want quick room-by-room loads and duct design on any device, priced per project or by subscription.

Price

$45 per project; Pro subscription $50 per user a month for unlimited Manual J, S and D.

Personal $45 /project Manual J Manual S Manual D
Quoted from the vendor pricing page on November 10, 2026.

Key features

• ACCA Manual J loads, Manual S equipment selection and Manual D duct design
• CoolCalc Scan app that builds a 3D floor plan with the LiDAR scanner on an iPhone 12 Pro or newer, or an iPad Pro
• Floor plan upload, satellite trace for block loads, and free-draw input
• Equipment selection database covering dozens of brands, from Carrier and Trane to Daikin and Mitsubishi
• Project sharing inside an organization or with outside users such as a HERS rater

Strengths and weaknesses

• Strength: Runs in any modern browser on Mac, PC, phone or tablet
• Strength: Build a project for free and pay only when you want the Manual J results
• Strength: Pay-per-project option suits low-volume contractors
• Weakness: Needs an internet connection except while scanning
• Weakness: Residential focus; no commercial ASHRAE loads
• Weakness: Proposal builder and CRM are on the Pro Plus plan, which was not yet available

Key facts

• Pay per use: $45 per project
• Subscription: Pro at $50 per user a month, unlimited Manual J, S and D
• Users: 150k+ users and 1M+ projects, per the vendor
• Platform: Web browser, plus the CoolCalc Scan iOS app

Where it ranks

CoolCalc is No. 2 in our Best HVAC Design Software verdict.