# Transformer Calculator. vs Building Wire Selector

The clearest difference is in-app purchases: Building Wire Selector at none against Transformer Calculator.'s 1. Building Wire Selector also leads on ads (none vs shown) and rating (5.0 vs 4.8). Transformer Calculator.'s advantage is ratings volume (49 vs 2). On price, update cadence, device support and iOS requirement there is nothing between them.

Both are free to download. Transformer Calculator. sells 1 one-off in-app purchase. Building Wire Selector asks for nothing beyond the download.

Building Wire Selector holds the better App Store score, 5.0 against 4.8. That said, the two scores are not equally well evidenced: Transformer Calculator. has 49 ratings behind it against 2, so its average is the more settled of the two.

Transformer Calculator. ships an update every 4 months, Building Wire Selector every 2 months. The most recent releases landed on October 27, 2026 and October 24, 2026 respectively.

## The numbers

| Metric | Transformer Calculator. | Building Wire Selector |
| --- | --- | --- |
| Price | Free | Free |
| Rating | [4.8 (49 ratings)](https://appshunter.io/ios/app/transformer-calculator/id1506155081/reviews) | **[5.0 (2 ratings)](https://appshunter.io/ios/app/building-wire-selector/id6670218338/reviews)** |
| Number of ratings | **49** | 2 |
| Positive reviews | — | 100.0% of reviews |
| In-app purchases | Yes | **No** |
| Ads | Yes | **No** |
| Update frequency | Every 4 months | **Every 2 months** |
| Monetization | Free with in-app purchases | **Free** |
| Size | 41 MB | 6 MB |
| Requires iOS | 17.6 | **16.6** |
| Devices | iPhone, iPad | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [V PUGAZHENTHI](https://appshunter.io/developer/491898049) | [Southwire Company](https://appshunter.io/developer/440338423) |

## What reviewers say

### Transformer Calculator.

[App page](https://appshunter.io/ios/app/transformer-calculator/id1506155081)

This app simplifies transformer calculations for engineers and students. It accurately computes primary and secondary currents, turns ratios, and secondary voltages based on user inputs for transformer ratings and winding turns.

**Highlights:** Primary and secondary current calculations, Turns ratio determination, Transformer type identification, Secondary voltage calculation, Supports 1Φ and 3Φ phases, User-friendly interface

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

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Go Pro | $3.99 | one-time |


### Building Wire Selector

[App page](https://appshunter.io/ios/app/building-wire-selector/id6670218338)

This tool helps determine the correct conductor size and wire type for electrical installations. It adheres to the National Electrical Code® wiring methods, ensuring compliance and safety.

**Highlights:** Conductor size determination, Wire and cable type selection, National Electrical Code compliance, Electrical installation guidance

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is Transformer Calculator. free?

Transformer Calculator. is free to download, with in-app purchases available.

### Is Building Wire Selector free?

Building Wire Selector is free to download, with no in-app purchases.

### Which has better reviews, Transformer Calculator. or Building Wire Selector?

Building Wire Selector is rated higher. Transformer Calculator. averages 4.8 out of 5 from 49 ratings, while Building Wire Selector averages 5.0 from 2 ratings.

### Do Transformer Calculator. or Building Wire Selector have ads?

Transformer Calculator. shows ads; Building Wire Selector does not.

### Which is updated more often, Transformer Calculator. or Building Wire Selector?

Transformer Calculator. ships an update every 4 months, and Building Wire Selector every 2 months. Most recently, Transformer Calculator. was updated on October 27, 2026 and Building Wire Selector on October 24, 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.*