# DuctSizeCalc vs 空気線図Pro 湿り空気線図・空調計算

The clearest difference is price: 空気線図Pro 湿り空気線図・空調計算 at Free against DuctSizeCalc's $2.99. 空気線図Pro 湿り空気線図・空調計算 also leads on update cadence (every 3 days vs every 58 months). DuctSizeCalc's advantage is in-app purchases (none vs 1) and ads (none vs shown). On device support there is nothing between them.

空気線図Pro 湿り空気線図・空調計算 is free to download; DuctSizeCalc costs $2.99 up front. 空気線図Pro 湿り空気線図・空調計算 sells 1 one-off in-app purchase. DuctSizeCalc asks for nothing beyond the download.

DuctSizeCalc ships an update every 58 months, 空気線図Pro 湿り空気線図・空調計算 every 3 days. The most recent releases landed on October 8, 2026 and October 6, 2026 respectively.

## The numbers

| Metric | DuctSizeCalc | 空気線図Pro 湿り空気線図・空調計算 |
| --- | --- | --- |
| Price | $2.99 | **Free** |
| Rating | **[2.0 (1 ratings)](https://appshunter.io/ios/app/ductsizecalc/id458032972/reviews)** | — |
| Number of ratings | **1** | — |
| Positive reviews | 0.0% of reviews | — |
| In-app purchases | **No** | Yes |
| Ads | **No** | Yes |
| Update frequency | Every 58 months | **Every 3 days** |
| Monetization | Paid | — |
| Size | 2 MB | 8 MB |
| Requires iOS | **9.0** | 18.2 |
| Devices | iPhone, iPod | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [Technical Data Service Co.,Ltd.](https://appshunter.io/developer/441746798) | [koichi hashimoto](https://appshunter.io/developer/1659408789) |

## What reviewers say

### DuctSizeCalc

[App page](https://appshunter.io/ios/app/ductsizecalc/id458032972)

Easily calculate duct sizes for air conditioning systems using the constant-pressure method. Input wind volume and tap calculate to determine duct dimensions, pressure, and wind velocity. Useful for blueprints, working drawings, and on-site applications.

**Highlights:** Constant-pressure method duct sizing, Input wind volume for calculation, Supports rectangular and circular ducts, Adjustable friction loss and wind velocity, Automatic height adjustment for WxH interlock, Metric system calculations

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

**In-app purchases:** none


### 空気線図Pro 湿り空気線図・空調計算

[App page](https://appshunter.io/ios/app/pro/id6792616333)

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

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| プレミアム | $5.99 | one-time |


## Frequently asked questions

### Is DuctSizeCalc free?

DuctSizeCalc costs $2.99, with no in-app purchases.

### Is 空気線図Pro 湿り空気線図・空調計算 free?

空気線図Pro 湿り空気線図・空調計算 is free to download, with in-app purchases available.

### Do DuctSizeCalc or 空気線図Pro 湿り空気線図・空調計算 have ads?

空気線図Pro 湿り空気線図・空調計算 shows ads; DuctSizeCalc does not.

### Which is updated more often, DuctSizeCalc or 空気線図Pro 湿り空気線図・空調計算?

DuctSizeCalc ships an update every 58 months, and 空気線図Pro 湿り空気線図・空調計算 every 3 days. Most recently, DuctSizeCalc was updated on October 8, 2026 and 空気線図Pro 湿り空気線図・空調計算 on October 6, 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.*