# Rafter Help — Roof Pitch + Length Calculator

> Roof pitch and rafter length calculator for construction. (iPhone/iPad app by Armchair Engineering.)

- Source: https://appshunter.io/ios/app/rafter-help/id1006188060 (this page in markdown: same URL + `.md`)
- Developer: [Armchair Engineering](https://appshunter.io/developer/398901339)
- Category: Utilities, Productivity
- Price: $1.99
- Rating: 4.50/5 from 212 App Store ratings · 25 written reviews indexed
- Age rating: 4+
- Requires: iOS 10.0 · 6 MB
- Languages: American English
- Released: 2015-06-25
- Data updated: 2026-09-09
- Monetization: free
- User reviews in markdown: https://appshunter.io/ios/app/rafter-help/id1006188060/reviews.md

## What is Rafter Help?

Rafter Help is the easiest way to calculate rafter length and associated values when building!

Quickly find roof pitch, rafter lengths and ridge height for gable roofs, based on room and ridge width. 
Or calculate length values with more control from the Advanced tab.

Features Include: 

- Accurately solve rafter equations
- Enter pitch steepness in radians, decimal degrees or degrees, minutes, seconds (DMS) or rise/run (e.g. 8/12)
- Enter lengths in mm, cm, inches or feet
- Select your preferred number of decimal places

## Key features

- 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

## Recent user reviews (10 of 25)

All indexed reviews: https://appshunter.io/ios/app/rafter-help/id1006188060/reviews.md

### 4/5 — Rafter Help

*2024-01-02, version 1.5.2*

Works great easy to understand

### 1/5 — Fake app can’t add 1/4 inch

*2023-11-10, version 1.5.2*

I want a refund.

### 1/5 — Don’t bother

*2023-02-07, version 1.5.2*

Inaccurate and unconvincing

### 5/5 — Awesome App but...

*2021-02-16, version 1.5.2*

This is an awesome app, but it is really limited

### 5/5 — Waste of money

*2021-01-26, version 1.5.2*

Not what I was hoping for. Doesn’t give any cut angles only lengths

### 1/5 — Don’t wast your money

*2020-10-31, version 1.5.2*

Doesn’t get you necessary measurements to cut rafters.

### 5/5 — Looks promising, but...

*2020-05-23, version 1.5.2*

Might be me, but where is the decimal point in the keypad? Ridge width is 2.5” ; no decimal available on the calc?  Hope I’m missing a mistake...

### 1/5 — Junk

*2020-03-29, version 1.5.2*

This can only do common rafters. No hip rafters etc what a waste of time.

### 3/5 — A major error

*2020-03-27, version 1.5.2*

I wouldn’t pay money for this app. It’s very simple. But also has a major error with the drawing of the basic gable, where the height (h) is meant to go down to the bottom of the birds mouth. Not the top of the top plate. I had to do my own calculations to work out what was wrong, which meant it made more work for me. They should resolve this issue and also make it free because it a very basic calculator with only 2 options and not enough information / calculations to really help a precision carpenter.

### 5/5 — Steve the chippy

*2020-03-16, version 1.5.2*

Great little app easy to use and accurate ,like the way it gives you the rafter length with the ridge deduction done for you .

## Frequently asked questions about Rafter Help

### What does Rafter Help do?

Rafter Help is a utility app designed to assist with roof construction. It allows users to quickly calculate rafter lengths and associated values, such as roof pitch and ridge height, for gable roofs.

### What are the key features of Rafter Help?

Key features include accurate solving of rafter equations, support for multiple pitch input formats (radians, decimal degrees, DMS, rise/run), flexible length unit selection (mm, cm, inches, feet), and the ability to choose the number of decimal places for results.

### Is Rafter Help free to use?

Yes, Rafter Help is a free application. It does not have any in-app purchases or advertisements, making it completely free for users.

### What kind of roofs can I calculate with this app?

The app is primarily designed for calculating measurements for gable roofs. It offers quick calculations for these structures and also includes an advanced tab for more controlled calculations.

### Who would benefit from using Rafter Help?

This app is ideal for builders, carpenters, and DIY enthusiasts involved in roof construction. It simplifies complex calculations, ensuring accuracy and efficiency in their projects.

## Version history (last 5 releases)

### 1.5.2 — 2019-11-08

- Fixed floating keyboard bug, present on some devices running iOS 13

### 1.5.1 — 2019-08-23

- Fixed a bug that prevented advanced view results from being display when inputing pitch angle as a rise/run value

### 1.5 — 2019-06-12

- New Advanced tab for more detailed calculations
- Improved rise/run angle input handling
- Bug fixes

### 1.4 — 2018-02-02

- iPhone X support

### 1.3.1 — 2016-10-04

- Added ability to measure roof pitch as rise/run (e.g. 8/12), available in settings along with exiting angle units
- iOS 10 support
- Bug fixes

## Apps similar to Rafter Help

| App | Rating | Price | Category |
| --- | --- | --- | --- |
| [RoofCalc - Roofing Calculator](https://appshunter.io/ios/app/roofcalc-roofing-calculator/id1014237429) | 4.0 (9) | Free | Utilities |
| [Roof Guide - Carpentry Calc](https://appshunter.io/ios/app/roof-guide-carpentry-calc/id920670842) | 4.1 (16) | Free | Utilities |
| [RedX Roof - Rafter Calculator](https://appshunter.io/ios/app/redx-roof-rafter-calculator/id1519896740) | 4.7 (850) | Free | Utilities |
| [Roof Calculator: Pitch, Angle](https://appshunter.io/ios/app/roof-calculator-pitch-angle/id1534675511) | 4.3 (33) | Free | Utilities |
| [Slope Calculator - Calc](https://appshunter.io/ios/app/slope-calculator-calc/id1561129699) | 4.3 (104) | Free | Utilities |
| [Span Calc](https://appshunter.io/ios/app/span-calc/id380481343) | 2.9 (15) | Free | Utilities |

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All apps by Armchair Engineering: https://appshunter.io/developer/398901339

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*Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-09-09.*