# Rafter Help vs Slope Calculator

The clearest difference is price: Slope Calculator at Free against Rafter Help's $1.99. Slope Calculator also leads on review sentiment (58% vs 40%). Rafter Help's advantage is in-app purchases (none vs 1) and update cadence (every 5 months vs every 14 months). On rating, ratings volume, ads and device support there is nothing between them.

Slope Calculator is free to download; Rafter Help costs $1.99 up front. Slope Calculator sells 1 one-off in-app purchase. Rafter Help asks for nothing beyond the download.

Rafter Help holds the better App Store score, 4.5 against 4.3. Both are backed by a comparable volume of ratings — 214 and 104 respectively. Written reviews complicate that: 40% of Rafter Help's written reviews are positive against 58% of Slope Calculator's, so the app with the better star average is not the one people write more warmly about.

Rafter Help ships an update every 5 months, Slope Calculator every 14 months. The most recent releases landed on October 26, 2026 and October 23, 2026 respectively.

## The numbers

| Metric | Rafter Help | Slope Calculator |
| --- | --- | --- |
| Price | $1.99 | **Free** |
| Rating | **[4.5 (214 ratings)](https://appshunter.io/ios/app/rafter-help/id1006188060/reviews)** | [4.3 (104 ratings)](https://appshunter.io/ios/app/slope-calculator-calc/id1561129699/reviews) |
| Number of ratings | **214** | 104 |
| Positive reviews | 40.0% of reviews | **58.3% of reviews** |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | **Every 5 months** | Every 14 months |
| Monetization | **Free** | Free with in-app purchases |
| Size | 6 MB | 5 MB |
| Requires iOS | **10.0** | 13.0 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Armchair Engineering](https://appshunter.io/developer/398901339) | [Phan Nhat Đang](https://appshunter.io/developer/1437390098) |

## What reviewers say

### Rafter Help

[App page](https://appshunter.io/ios/app/rafter-help/id1006188060)

This app simplifies roof construction by calculating rafter lengths and related measurements. It supports various input formats for pitch and length, offering both quick calculations for gable roofs and advanced control for more complex needs.

**Highlights:** Calculate rafter length and associated values, Determine roof pitch, rafter lengths, and ridge height, Supports gable roofs, Advanced calculation options, Multiple input formats for pitch (radians, degrees, DMS, rise/run), Flexible length units (mm, cm, inches, feet), Customizable decimal places

**Features:** Vision Pro support

**In-app purchases:** none

**What reviewers like**

- 👍 Easy to understand
- 👍 Accurate measurements
- 👍 Gives rafter length with deduction
- 👍 Useful for setting out measurements
- 👍 First class, use it all the time

**What reviewers complain about**

- 👎 Cannot add 1/4 inch
- 👎 Inaccurate and unconvincing
- 👎 Really limited functionality
- 👎 Doesn’t give cut angles, only lengths
- 👎 Doesn’t give necessary measurements for rafters

**Reported bugs**

- Cannot add 1/4 inch
- Missing decimal point on keypad
- Major error in basic gable drawing
- App won't open, says 'waiting'

**Requested features**

- Add 1/4 inch input
- Provide cut angles
- Include decimal point on keypad
- Support hip rafters
- Correct drawing error for basic gable


### Slope Calculator

[App page](https://appshunter.io/ios/app/slope-calculator-calc/id1561129699)

Calculate slope in angle, percentage, or ratio by inputting two sides of a right triangle. This intuitive and easy-to-use application provides the remaining necessary values.

**Highlights:** Calculate slope as angle, Calculate slope as percentage, Calculate slope as ratio, Input two sides of a right triangle, Calculate remaining triangle values, Intuitive and easy to use

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

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Remove ads | $1.99 | one-time |


## Frequently asked questions

### Is Rafter Help free?

Rafter Help costs $1.99, with no in-app purchases.

### Is Slope Calculator free?

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

### Which has better reviews, Rafter Help or Slope Calculator?

Rafter Help is rated higher. Rafter Help averages 4.5 out of 5 from 214 ratings, while Slope Calculator averages 4.3 from 104 ratings.

### Do Rafter Help or Slope Calculator have ads?

Neither Rafter Help nor Slope Calculator shows ads.

### Which is updated more often, Rafter Help or Slope Calculator?

Rafter Help ships an update every 5 months, and Slope Calculator every 14 months. Most recently, Rafter Help was updated on October 26, 2026 and Slope Calculator on October 23, 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.*