# Southwire® Voltage Drop Calc vs NEMA Guide

The clearest difference is update cadence: NEMA Guide at every 2 days against Southwire® Voltage Drop Calc's every 2 months. NEMA Guide also leads on rating (5.0 vs 4.6). Southwire® Voltage Drop Calc's advantage is ratings volume (1.5K vs 1) and iOS requirement (15.0 vs 17.6). On price, ads, in-app purchases and monetization model there is nothing between them.

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

NEMA Guide holds the better App Store score, 5.0 against 4.6. That said, the two scores are not equally well evidenced: Southwire® Voltage Drop Calc has 1.5K ratings behind it against 1, so its average is the more settled of the two.

Southwire® Voltage Drop Calc ships an update every 2 months, NEMA Guide every 2 days. The most recent releases landed on November 6, 2026 and October 30, 2026 respectively.

## The numbers

| Metric | Southwire® Voltage Drop Calc | NEMA Guide |
| --- | --- | --- |
| Price | Free | Free |
| Rating | [4.6 (1.5K ratings)](https://appshunter.io/ios/app/southwire-voltage-drop-calc/id440338420/reviews) | **[5.0 (1 ratings)](https://appshunter.io/ios/app/nema-guide/id6746103301/reviews)** |
| Number of ratings | **1.5K** | 1 |
| Positive reviews | 49.1% of reviews | — |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 2 months | **Every 2 days** |
| Monetization | Free | Free |
| Size | 10 MB | 23 MB |
| Requires iOS | **15.0** | 17.6 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [Southwire Company](https://appshunter.io/developer/440338423) | [Red Zepp LLC](https://appshunter.io/developer/1812216821) |

## What reviewers say

### Southwire® Voltage Drop Calc

[App page](https://appshunter.io/ios/app/southwire-voltage-drop-calc/id440338420)

Calculate the appropriate wire size for electrical circuits. This tool helps determine wire size based on voltage drop and current carrying capacity, ensuring compliance with NEC ampacity limits.

**Highlights:** Determine wire size for voltage drop, Calculate voltage drop for conductor runs, Limit wire size by voltage drop, Limit wire size by NEC ampacity, Supports AWG and KCMIL sizes

**Features:** macOS Compatibility

**In-app purchases:** none

**What reviewers like**

- 🚀 Quick and useful
- 🚀 Great Quick Reference
- 👍 A must have app for electricians
- 👍 Love These
- 👍 Electrical Engineer

**What reviewers complain about**

- 🐛 Motor starting Voltage drop
- 🐛 Useless!
- 🐛 Won't work
- 🐛 How to use
- 🐛 Confused

**Reported bugs**

- Useless!
- Won't work
- How to use
- Confused
- Bad app

**Requested features**

- Motor starting Voltage drop calculation
- Metric wire size options


### NEMA Guide

[App page](https://appshunter.io/ios/app/nema-guide/id6746103301)

Quickly identify and cross-reference NEMA plug and receptacle configurations with detailed illustrations and specifications. This tool streamlines the process for electricians and electrical professionals by allowing searches by NEMA number or filtering by various electrical parameters.

**Highlights:** Identify NEMA plug and receptacle configurations, Search by NEMA number, Filter by voltage, amperage, phase, poles, wires, and grounding, View matching configurations instantly, Over 170 configuration illustrations, Detailed specifications for each configuration, Offline data storage

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is Southwire® Voltage Drop Calc free?

Southwire® Voltage Drop Calc is free to download, with no in-app purchases.

### Is NEMA Guide free?

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

### Which has better reviews, Southwire® Voltage Drop Calc or NEMA Guide?

NEMA Guide is rated higher. Southwire® Voltage Drop Calc averages 4.6 out of 5 from 1.5K ratings, while NEMA Guide averages 5.0 from 1 ratings.

### Do Southwire® Voltage Drop Calc or NEMA Guide have ads?

Neither Southwire® Voltage Drop Calc nor NEMA Guide shows ads.

### Which is updated more often, Southwire® Voltage Drop Calc or NEMA Guide?

Southwire® Voltage Drop Calc ships an update every 2 months, and NEMA Guide every 2 days. Most recently, Southwire® Voltage Drop Calc was updated on November 6, 2026 and NEMA Guide on October 30, 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.*