# HVAC ResLoad vs Ductulator

The clearest difference is price: Ductulator at $3.99 against HVAC ResLoad's $199.99. Ductulator also leads on rating (4.7 vs 3.4) and ratings volume (361 vs 8). HVAC ResLoad's advantage is iOS requirement (15.6 vs 18.6). On review sentiment, ads, in-app purchases and device support there is nothing between them.

HVAC ResLoad costs $199.99 and Ductulator $3.99 up front. Neither carries in-app purchases, so what you see is what you pay.

Ductulator holds the better App Store score, 4.7 against 3.4. That said, the two scores are not equally well evidenced: Ductulator has 361 ratings behind it against 8, so its average is the more settled of the two. Written reviews split almost evenly too, at 50% and 50% positive.

HVAC ResLoad ships an update every 4 months, Ductulator every 2 months. The most recent releases landed on October 29, 2026 and November 3, 2026 respectively.

## The numbers

| Metric | HVAC ResLoad | Ductulator |
| --- | --- | --- |
| Price | $199.99 | **$3.99** |
| Rating | [3.4 (8 ratings)](https://appshunter.io/ios/app/hvac-resload-j/id567612484/reviews) | **[4.7 (361 ratings)](https://appshunter.io/ios/app/ductulator-duct-sizing/id1474939475/reviews)** |
| Number of ratings | 8 | **361** |
| Positive reviews | 50.0% of reviews | 50.0% of reviews |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 4 months | **Every 2 months** |
| Monetization | Paid | **Free** |
| Best chart rank | — | **#123** |
| Size | 23 MB | 1 MB |
| Requires iOS | **15.6** | 18.6 |
| Devices | iPad | **iPhone, iPad** |
| Age rating | 4+ | 4+ |
| Developer | [Carmel Software Corporation](https://appshunter.io/developer/317970398) | [Wassim Murr](https://appshunter.io/developer/1474939474) |

## What reviewers say

### HVAC ResLoad

[App page](https://appshunter.io/ios/app/hvac-resload-j/id567612484)

Perform ACCA Manual J8 load calculations for residential and small commercial buildings. Generate and email PDF reports for clients and building officials. Includes extensive weather and construction data for detailed analysis.

**Highlights:** ACCA Manual J8 load calculations, Field-based cooling and heating load calculations, Emailable PDF reports, Unlimited projects and templates, Global weather data, Extensive construction data, Room-by-room analysis

**Features:** macOS Compatibility, Vision Pro support

**In-app purchases:** none


### Ductulator

[App page](https://appshunter.io/ios/app/ductulator-duct-sizing/id1474939475)

**Currently charting:** #123 Top Paid · Productivity (US App Store)

Instantly calculate HVAC duct sizes based on airflow, friction rate, or velocity. This tool provides accurate duct dimensions in seconds without needing charts, supporting various duct types and units.

**Highlights:** Instant duct sizing, Friction rate or velocity calculation, Multiple valid duct dimensions, IP and SI units support, Detailed sizing mode, Rectangular, circular, and flexible ducts

**Features:** macOS Compatibility, Vision Pro support

**In-app purchases:** none

**What reviewers like**

- 👍 Very helpful for duct sizing
- 👍 Easy to use in the field
- 👍 Saves time
- 👍 Seamless imperial/metric transitions
- 👍 Excellent tool for duct design

**What reviewers complain about**

- 👎 App should be free
- 👎 Functionality is pointless for some needs
- 👎 Doesn't help with traditional residential HVAC duct sizing
- 👎 App is a scam
- 👎 Decimal point doesn't work

**Reported bugs**

- Decimal point doesn't work on calculator
- New flex option isn't working properly
- Friction rate can't be changed in the latest version
- Skips duct sizes (e.g., 24-26)

**Requested features**

- Ability to pick duct size and see CFM
- Include flat oval ducts
- Option to select round or square duct
- Ability to enter duct size and get CFM
- Option for flex duct


## Frequently asked questions

### Is HVAC ResLoad free?

HVAC ResLoad costs $199.99, with no in-app purchases.

### Is Ductulator free?

Ductulator costs $3.99, with no in-app purchases.

### Which has better reviews, HVAC ResLoad or Ductulator?

Ductulator is rated higher. HVAC ResLoad averages 3.4 out of 5 from 8 ratings, while Ductulator averages 4.7 from 361 ratings.

### Do HVAC ResLoad or Ductulator have ads?

Neither HVAC ResLoad nor Ductulator shows ads.

### Which is updated more often, HVAC ResLoad or Ductulator?

HVAC ResLoad ships an update every 4 months, and Ductulator every 2 months. Most recently, HVAC ResLoad was updated on October 29, 2026 and Ductulator on November 3, 2026.

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*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*