# Proportion Solver

> Tool for solving mathematical proportions and conversions. (iPhone/iPad app by Ryan Ashcraft.)

- Source: https://appshunter.io/ios/app/proportion-solver/id325357198 (this page in markdown: same URL + `.md`)
- Developer: [Ryan Ashcraft](https://appshunter.io/developer/322118384)
- Category: Utilities, Education
- Price: Free
- Rating: 4.40/5 from 16 App Store ratings · 35 written reviews indexed
- Age rating: 4+
- Requires: iOS 9.0 · 17 MB
- Languages: American English
- Released: 2009-08-05
- Data updated: 2026-06-10
- Monetization: free
- User reviews in markdown: https://appshunter.io/ios/app/proportion-solver/id325357198/reviews.md

## What is Proportion Solver?

Proportion Solver is a simple, convenient tool to solve proportions. Proportions are useful for computing a value based on numerical relationships (e.g. width/height, Fahrenheit/Celsius, mph/meters, U.S. Dollars/Euros, pixels/inches).

## Key features

- Solve proportions
- Calculate based on numerical relationships
- Unit conversions
- Scaling calculations

## Recent user reviews (10 of 35)

All indexed reviews: https://appshunter.io/ios/app/proportion-solver/id325357198/reviews.md

### 5/5 — I use this app daily!  Love the simplicity!

*2021-02-28, version 3.1*

I have not written an app review in a decade. But I wanted to give the developers a big thank you for such a clean simple and extremely useful everyday app.  And thank you so much for updating this app to work with the latest iOS and iPhone 12 Pro.  There was a period of time where it wasn’t compatible and thus wouldn’t even allow me to install it...I was super bummed because I literally use this app everyday.  I looked for alternatives and quickly became annoyed that there really aren’t any. 

I absolutely love this app, thank you for continuing to support it!!

### 1/5 — Potential to be Amazing

*2018-02-25, version 3.1*

If we could assume that some of the people wanting this app (like myself) were idiots and provide some basic info on using this it would be amazing. I know the tasks I could use this for but not the slightest idea how to achieve it using this app. The screenshot previews provide no help either. In fact they only further the confusion. For example. The x sign in the second screenshot top right field. How is that there? I assumed if I hit the +/- button I could get there but alas, no dice. Please help. I went to your website for help and then tried to find a contact form. I don't use Twitter or Google plus so that brings me back to here.

### 5/5 — The best Ratio Calculator

*2017-11-25, version 3.1*

I use this for resin ratios in my workshop, one of my most used apps. It would be wonderful if there was Apple Watch support so I could ask my watch to calculate ratios while using gloves and operating equipment.

### 5/5 — Absolutely Perfect

*2017-09-13, version 3.0*

If you regularly deal with proportional scaling of very large or very small things this is a perfect tool that eliminates cumulative errors that creep into complex scaling. 

No frills, no preconceived or assumed ways it will be used. Just a simple and effective solution to an annoying task.

### 5/5 — Love the color scheme!

*2017-08-15, version 3.0*

Reminds me of the original Apple watch bands ;)

### 4/5 — Please Offer Ad Free Version

*2017-01-20, version 3.0*

Pretty cool app ... except for the ads. I would happily give you 99 cents to remove the ads.

**Developer response:** There are no ads in this app.

### 5/5 — It's great!

*2016-06-22, version 3.0*

This made my life so much easier!

### 5/5 — Finally

*2015-12-29, version 3.0*

Thanks for fixing this app. I use it all the time.

### 5/5 — Coffee Brewing Ratio

*2015-11-11, version 3.0*

Use this app all the time when calculating how much coffee to water to use. So happy it works in iOS 9 now.

### 5/5 — Best coffee app

*2015-11-03, version 3.0*

Thanks for the update!

## Frequently asked questions about Proportion Solver

### What does Proportion Solver do?

Proportion Solver is a tool designed to help users solve mathematical proportions. It assists in calculating unknown values when you have a known numerical relationship between quantities.

### What kind of calculations can I do with this app?

You can use this app to solve proportions for various scenarios, such as converting between different units (like Fahrenheit to Celsius or USD to Euros), scaling dimensions (like width to height), or calculating speeds (like mph to meters).

### Is Proportion Solver free to use?

Yes, Proportion Solver is a free application. There are no costs associated with downloading or using its core functionality.

### What are some common use cases for Proportion Solver?

Common use cases include scaling recipes, converting currency, calculating distances based on speed and time, or adjusting image dimensions. Essentially, any situation requiring a proportional calculation can benefit from this tool.

## Version history (last 5 releases)

### 3.1 — 2017-11-20

This app has been updated by Apple to display the Apple Watch app icon.

- Added support for iPhone X

### 3.0 — 2015-10-26

- Added support for iOS 9
- New design with a dynamically-scalable interface that supports all iPhone and iPad screen sizes
- Improved accessibility

### 2.1 — 2010-07-26

- Now designed for iPhone, iPod touch, and iPad
- High resolution graphics for iPhone 4 Retina display
- Multitasking support for compatible iOS 4 devices
- Various minor improvements

### 2.0 — 2010-04-02

- New interface and keyboard
- Support for copying results to the iPhone clipboard
- Improved formatting of results
- Improved error detection

### 1.1 — 2009-08-16

• Input fields don't automatically clear upon selection
• Minor UI changes
• Other minor bug fixes

## Apps similar to Proportion Solver

| App | Rating | Price | Category |
| --- | --- | --- | --- |
| [Lensit](https://appshunter.io/ios/app/lensit/id1468948972) | — | Free | Utilities |
| [Simplify Fractions](https://appshunter.io/ios/app/simplify-fractions/id1569741008) | 4.3 (3) | Free | Utilities |
| [Area Calculator - Area Finder](https://appshunter.io/ios/app/area-calculator-area-finder/id1540035634) | 1.8 (5) | Free | Utilities |
| [Area Volume Calculator](https://appshunter.io/ios/app/area-volume-calculator/id1051276090) | 4.1 (14) | Free | Utilities |
| [Rule of Three Calculator](https://appshunter.io/ios/app/rule-of-three-calculator/id1185318300) | 2.3 (4) | Free | Utilities |
| [SSI Steel Design](https://appshunter.io/ios/app/ssi-steel-design/id1474838160) | 3.0 (1) | Free | Utilities |

---

*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 2026-06-10.*