# Ductulator vs Smartuli

The clearest difference is price: Smartuli at Free against Ductulator's $3.99. Smartuli also leads on iOS requirement (15.1 vs 18.6). Ductulator's advantage is chart position (#39 vs unranked). On update cadence, ads, in-app purchases and device support there is nothing between them.

Smartuli is free to download; Ductulator costs $3.99 up front. Neither carries in-app purchases, so what you see is what you pay.

Both ship on a similar rhythm, roughly every 2 months. The most recent releases landed on September 22, 2026 and September 9, 2026 respectively.

## The numbers

| Metric | Ductulator | Smartuli |
| --- | --- | --- |
| Price | $3.99 | **Free** |
| Rating | **[4.7 (317 ratings)](https://appshunter.io/ios/app/ductulator-duct-sizing/id1474939475/reviews)** | — |
| Number of ratings | **317** | — |
| Positive reviews | 50.0% of reviews | — |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 2 months | Every 2 months |
| Monetization | Free | — |
| Best chart rank | **#39** | — |
| Size | 1 MB | 24 MB |
| Requires iOS | 18.6 | **15.1** |
| Devices | iPhone, iPad | **iPhone, iPad, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [Wassim Murr](https://appshunter.io/developer/1474939474) | [Ilia Manizhashvili](https://appshunter.io/developer/1802681433) |

## What reviewers say

### Ductulator

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

**Currently charting:** #39 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


### Smartuli

[App page](https://appshunter.io/ios/app/smartuli/id6482978577)

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is Ductulator free?

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

### Is Smartuli free?

Smartuli is free to download, with no in-app purchases.

### Do Ductulator or Smartuli have ads?

Neither Ductulator nor Smartuli shows ads.

### Which is updated more often, Ductulator or Smartuli?

Ductulator ships an update every 2 months, and Smartuli every 2 months. Most recently, Ductulator was updated on September 22, 2026 and Smartuli on September 9, 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.*