Best HVAC Load Calculation Software (2026)

For residential contractors choosing a Manual J tool. We compared six products on how they calculate, what you feed them, what they give back, and what they cost, using only what each vendor publishes. Every fact links to its source and was checked on October 16, 2026.

Disclosure: Tradewright is our product. We have tried to describe every other tool generously and accurately. If something here is out of date, tell us and we will fix it.

Updated October 16, 2026Written by the Tradewright team. Tradewright makes one of the products compared here; we say so wherever it matters.

How we compared these tools (methodology)

We looked at the same things for every product, using only the vendor's public website, its official app store listing and ACCA's public list. We did not use paid trials or private pricing.

Calculation method and ACCA status. What method the vendor says it uses, and whether the product appears on ACCA's approved software page (checked 2026-10-16). That page lists products by name without version numbers, and has Manual J and Manual D sections but no Manual S section.
Inputs. LiDAR or 3D capture, plan or PDF upload, drawing by hand, and reading existing equipment from a nameplate photo.
Outputs. Room-by-room Manual J, Manual S equipment selection, Manual D duct design, and hydronic design.
Proposal and closing. Good/Better/Best options, e-signature and payment.
Platforms and price. Where it runs, and the price exactly as listed. If a vendor does not list a price, we say "not publicly listed".

"Not stated" in the table means we could not find the feature on the vendor's public site. It does not mean the product cannot do it.

Summary table

HVAC load calculation software compared feature by feature, checked October 16, 2026
	Tradewright	Conduit	Cool Calc	Wrightsoft RSU	Elite RHVAC	Kwik Model 3D
Room-by-room Manual J	Yes	Yes	Manual J (room-by-room not stated)	Manual J (room-by-room not stated)	Yes	EAGLE edition, via EnergyGauge Loads
On ACCA's approved software listManual J section, checked 2026-10-16	Not yet; built on ACCA methods	Listed (Conduit Tech)	Listed (Cool Calc Manual J)	Listed (Right-J8)	Listed (RHVAC)	Not listed by name; its engine, FSEC EnergyGauge, is listed
LiDAR / 3D capture	LiDAR on iPhone/iPad	LiDAR on iPad Pro	LiDAR via CoolCalc Scan (iPhone 12 Pro+ / iPad Pro)	Not stated	Not stated	3D modelling by hand (no LiDAR)
Plan upload	Yes	Blueprint import (iPad app)	Yes	PDF and CAD import	Drawing Board add-on (draw plans)	2D plan import (KESTREL)
Existing equipment from nameplate photo	Yes	Not stated	Not stated	Not stated	Not stated	Not stated
Manual S equipment selection	Yes	Sizing guidance and equipment selection	Yes	Yes	Yes	Equipment selection (EAGLE)
Manual D duct design	No	Not stated	Yes (ACCA-listed, with exclusions)	Yes (Right-D)	Yes	Duct design (EAGLE, KESTREL)
Whole-system 15-year comparison	Yes	Not stated	Not stated	ROI/payback in Right-Mobile Consultant	Not stated	Not stated
Good/Better/Best proposal	Yes	Not stated	Proposal Builder listed as coming (Pro Plus)	In Right-Mobile Consultant	Proposals via Proposal Maker	Not stated
E-signature and payment	Yes	Not stated	Not stated	Not stated	Not stated	Not stated
Boilers / radiators / hydronic	Boiler options and room heat loss for radiator homes	Not stated	Not stated	Hydronic, radiant and geothermal design	Radiant floor tubing length	Not stated
Platforms	iPhone and iPad, plus browser	iPad app	Web browser, plus iOS scan app	Windows (plus browser-based mobile tools)	Windows desktop; Rhvac Online in a browser	Windows (EAGLE); Mac or Windows (KESTREL)
Price (listed)	From $199/seat/mo	Not publicly listed	$45/project or $50/user/mo	$900/yr (Residential package)	$599 desktop licence or $239/yr online	$299/yr (EAGLE); $199/yr (KESTREL)

Checked October 16, 2026 against each vendor's public site and ACCA's approved software list. "Not stated" means not found on the public site, not that the feature is missing. Prices change; see each vendor's page.

Which load calculation software fits you?

Start here. The per-product notes below back up each recommendation.

If you…
need a quick, affordable Manual J for a permit or a one-off job
Cool Calc's pay-per-project plan or its Pro plan runs in a browser and is on ACCA's list. Our free Manual J calculator gives a rough estimate first, but it is not a substitute for a room-by-room Manual J. Learn more
If you…
design full duct or hydronic systems in the office
Wrightsoft Right-Suite Universal or Elite RHVAC cover Manual J, S and D with deep engineering inputs. Kwik Model 3D is worth a look for to-scale duct layouts. Learn more
If you…
want a fast LiDAR scan and an ACCA-listed Manual J on an iPad, and already run ServiceTitan
Conduit is built for that, and ServiceTitan has announced it is acquiring Conduit Tech.
If you…
sell at the kitchen table and need the proposal, signature and payment too
Tradewright takes you from scan to room-by-room Manual J, Manual S, a 15-year whole-system comparison and a signed Good/Better/Best from your own price book, in one visit. Learn more
If you…
sell a lot of heat pumps into boiler and radiator homes
Tradewright compares heat pump, boiler, furnace, mini-split and dual-fuel side by side and shows what was ruled out and why. Learn more

Tradewright

Our product

Design and proposal in one visit: scan, room-by-room Manual J, Manual S, a whole-system comparison and a signed Good/Better/Best.

Best for: Replacement contractors who sell in the home and want the engineering and the signed proposal in the same visit.

Strengths

LiDAR scan on iPhone or iPad, or plan upload, with geometry you can correct
Existing equipment read from a nameplate photo
Room-by-room Manual J and Manual S selection from real equipment
Heat pump, boiler, furnace, mini-split and dual-fuel compared on 15-year cost of ownership, with ruled-out options and why
Good/Better/Best priced from your own price book, with e-signature, payment and financing at the table
Works with Housecall Pro, Jobber, FieldEdge, ServiceTitan or no CRM

Limits

Not yet on ACCA's approved Manual J software list (built on ACCA Manual J and Manual S methods)
No Manual D duct design
Higher monthly price than load-calc-only tools, because it includes the proposal and closing
Built for residential replacement, not commercial or new-construction plan takeoffs

Price (as publicly listed): Starter $199/seat/mo; Pro $349/seat/mo plus $500/mo platform fee; Enterprise custom source · website

Conduit

iPad LiDAR scanning and room-by-room Manual J in the home, with 3D and AR visuals.

Best for: Contractors who want a fast, in-home LiDAR scan and an ACCA-listed Manual J on an iPad Pro.

Strengths

Room-by-room Manual J; listed on ACCA's approved software page
3D model from iPad Pro LiDAR in about 10 minutes, per Conduit, plus 2D floor plans and AR equipment placement
Equipment selection guidance and Manual S sizing targets (per its App Store release notes)
ServiceTitan connection; ServiceTitan announced an agreement to acquire Conduit Tech in September 2025

Limits

Pricing is not publicly listed (custom pricing through a demo)
App listed for iPad and Apple Vision; iPhone, Android and Windows are not stated
Good/Better/Best proposals, e-signature and payments are not described in detail on its site

Price (as publicly listed): Not publicly listed source · website

Cool Calc

Browser-based Manual J, S and D with LiDAR scanning, plan upload and satellite trace.

Best for: Contractors and designers who want an affordable, ACCA-listed Manual J that runs in any browser, including for permits.

Strengths

Built on ACCA Manual J, S and D; listed on ACCA's page for Manual J, and for Manual D with stated exclusions
Runs in any modern browser on Mac, PC, phone or tablet
Several ways to enter a house: CoolCalc Scan LiDAR app (iPhone 12 Pro or later, iPad Pro), floor plan upload, satellite trace, free-draw
Pay-per-project option for occasional users

Limits

Proposal Builder, CRM and ServiceTitan/Housecall Pro integrations are listed under Pro Plus, marked as coming soon on its site
E-signature and payments not stated
No Android app listed

Price (as publicly listed): Personal $45 per project; Pro $50 per user per month; Pro Plus $250 per user per month (listed as coming soon) source · website

Wrightsoft Right-Suite Universal

A full Windows design suite: loads, equipment, ducts, hydronic and radiant, CAD, and parts-based proposals. Part of MiTek.

Best for: Design departments and engineers who lay out complete duct or hydronic systems in the office.

Strengths

Manual J, Manual S and Manual D in one program; Right-J8 and Right-D are on ACCA's list
Duct, hydronic, radiant and geothermal loop design
PDF and CAD (DWG/DXF) import for tracing plans
Right-Proposal builds proposals from your own parts and pricing; Right-Mobile Consultant adds Good/Better/Best and ROI in a browser

Limits

Right-Suite Universal runs on Windows; in-home selling is a separate browser product
No LiDAR capture stated
E-signature and payments not stated

Price (as publicly listed): Residential package $900/yr; Right-Mobile Consultant $300/yr; Right-J Mobile $150/yr; other add-ons listed source · website

Elite Software RHVAC

Long-standing room-by-room Manual J, with Manual S and Manual D, on Windows or in a browser.

Best for: Designers who want a one-time desktop licence and deep engineering inputs and reports.

Strengths

Block and room-by-room loads per ACCA Manual J 8th Edition; RHVAC is on ACCA's list
Manual S equipment selection report using manufacturer performance data, and Manual D duct sizing
Permanent desktop licence option, plus Rhvac Online that runs on iPads, tablets, computers and phones
Fills in ACCA Form 310 and other reports automatically, per Elite

Limits

No LiDAR capture stated; plan drawing is a desktop add-on
Proposals come from a separate product (Proposal Maker); Good/Better/Best and e-signature not stated

Price (as publicly listed): Rhvac 10 desktop $599 (permanent licence); Rhvac Online $239 for 1 year source · website

Kwik Model 3D

Game-style 3D house modelling for loads, equipment selection and realistic duct layouts.

Best for: Designers who want to model ducts to scale with a fittings library, with or without their own load software.

Strengths

EAGLE edition does load calcs via FSEC EnergyGauge Loads (on ACCA's list), equipment selection and duct design
KESTREL edition designs ducts using loads from other software, with 2D plan import and CubiCasa 3D import
To-scale flex and rigid duct design with a parts list export

Limits

Kwik Model itself is not listed by name on ACCA's page; its load engine is
No LiDAR capture, proposals, e-signature or payments stated
EAGLE installs on Windows

Price (as publicly listed): EAGLE $299 for a 1-year licence; KESTREL $199 for a 1-year licence (introductory) source · website

Questions

What is the best Manual J software?

It depends on the job. For an affordable, browser-based Manual J for permits, Cool Calc is a strong choice. For full office design including ducts and hydronic, Wrightsoft and Elite RHVAC are established tools. For a fast iPad LiDAR scan, Conduit. If you need the load, equipment selection and a signed proposal in one visit, that is what Tradewright is built for. Tradewright is our product.

Is there free Manual J software?

Free calculators exist, including ours, but they give whole-house estimates, not a room-by-room Manual J. Cool Calc lets you pay per project ($45 as listed on October 16, 2026) instead of subscribing. For permits and rebates you generally need a full room-by-room calculation.

Which Manual J software is ACCA-approved?

ACCA keeps the official list on its approved software page. On October 16, 2026 its Manual J section included Wrightsoft Right-J8, Elite RHVAC, Cool Calc Manual J and Conduit Tech, among others. Kwik Model 3D uses FSEC EnergyGauge Loads, which is listed. Always check ACCA's page for the current list.

Is Tradewright ACCA-approved?

Not yet. Tradewright is not on ACCA's list of approved Manual J software. Our load calculations follow the ACCA Manual J (8th edition) and Manual S methods, every input is visible, and reports show the assumptions behind each number. We plan to apply for ACCA approval in 2028 and will update this answer when that status changes.

Do I need Manual D?

If you are installing new ductwork or changing the duct system, a Manual D duct design is how you size it properly, and some jurisdictions and programs ask for it. For a like-for-like equipment swap on existing ducts, many contractors check static pressure and airflow instead. Tradewright does not do Manual D; Wrightsoft, Elite, Cool Calc and Kwik Model 3D offer duct design.

Can I run Manual J on an iPad?

Yes. Conduit and Tradewright run as apps with LiDAR scanning, Cool Calc runs in the iPad browser with a separate iOS scan app, and Elite says Rhvac Online runs on iPads. Wrightsoft Right-Suite Universal itself is a Windows program.

Is measureQuick a Manual J tool?

measureQuick is mainly known for diagnostics and commissioning rather than load calculation and design, so we did not include it in this comparison. Check its website for its current features.

How often is this comparison updated?

We re-check every vendor fact and price before each update and show the date at the top. This version was checked on October 16, 2026.

Sources

ACCA: Approved software (Manual J and Manual D lists) (accessed 2026-10-16)
Conduit home page (accessed 2026-10-16)
Conduit: Load calculations (accessed 2026-10-16)
Conduit: Pricing (accessed 2026-10-16)
Conduit: Platform (ServiceTitan integration) (accessed 2026-10-16)
Conduit HVAC Toolkit on the App Store (accessed 2026-10-16)
ServiceTitan: ServiceTitan acquires Conduit Tech (accessed 2026-10-16)
ServiceTitan: Conduit Tech acquisition press release (accessed 2026-10-16)
Cool Calc home page (features and plans) (accessed 2026-10-16)
CoolCalc Scan on the App Store (accessed 2026-10-16)
Wrightsoft: Right-Suite Universal (accessed 2026-10-16)
Wrightsoft: FAQ (accessed 2026-10-16)
Wrightsoft: Store (prices) (accessed 2026-10-16)
Wrightsoft: Mobile in-home selling (Right-Mobile Consultant) (accessed 2026-10-16)
Wrightsoft: CAD and PDF files in Right-Draw (accessed 2026-10-16)
Elite Software: Rhvac information and prices (accessed 2026-10-16)
Kwik Model 3D home page (accessed 2026-10-16)
Kwik Model 3D: About (EAGLE and KESTREL) (accessed 2026-10-16)
Kwik Model 3D: Purchase (accessed 2026-10-16)

Related tools and guides

Manual J: the complete guideWhat it is, the inputs, and how to read the report.Manual J software in TradewrightRoom-by-room loads from a LiDAR scan or plan.Free Manual J calculator (estimate)A quick whole-house estimate with the limits spelled out.Best HVAC proposal software (2026)OnCall Air, Housecall Pro, ServiceTitan, FieldEdge, PandaDoc and Tradewright.Conduit alternativeConduit and Tradewright, side by side.Cool Calc alternativeCool Calc and Tradewright, side by side.

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