# EQD Calculator

> Radiation oncology tool for calculating Biologically Effective Dose (BED) and Equivalent Dose (EQD). (iPhone/iPad app by Hiroyuki KATOH.)

- Source: https://appshunter.io/ios/app/eqd-calculator/id898546583 (this page in markdown: same URL + `.md`)
- Developer: [Hiroyuki KATOH](https://appshunter.io/developer/898546586)
- Category: Medical, Education
- Price: Free
- Rating: 4.40/5 from 7 App Store ratings · 4 written reviews indexed
- Age rating: 17+
- Requires: iOS 8.0 · 15 MB
- Languages: American English
- Released: 2014-07-20
- Data updated: 2026-06-10
- Monetization: free
- User reviews in markdown: https://appshunter.io/ios/app/eqd-calculator/id898546583/reviews.md

## What is EQD Calculator?

In practice of radiotherapy, do you often want to check easily the BED and EQD?
We considered that it is wonderful to calculate them with iPhone, iPod and iPad that we carry always.
That’s why we designed new App “EQD calculator”.
Considering use in practice, primary concept of design is easy to use and quick to get the results.
In practice, we think that EQD is more useful than directly use of BED, so we named this App as “EQD Calculator”.
Please try EQD calculator!

We have released “TDF Calculator” that is capable to calculate the TDF factor defined by Orton et al.
Please, try also “TDF Calculator”. 
See “View More by This Developer” appeared above. 

#Strong points
- This App is designed for the professionals working in the field of Radiation Oncology.
- Although there are a lot of numbers on the screen, this App is designed to look like a table calculation, therefore you can understand easily the indication of each values.
- You can refer alpha/beta ratio and tolerance dose tables in this App.
- You can organize this App with URL scheme (jp.37.EQDcalculator://) in other App such as launchers. 

#Main features
- This App calculates Biologically Effective Dose (BED) defined by Linear-Quadratic (LQ) model. Additionally, this App can calculate Equivalent Dose (EQD) in indicating fraction dose simultaneously.
- This App can also calculate the fraction dose which is equivalent in indicating fractionation times. Therefore, when you need to change the schedule of radiotherapy, you can keep the influences of change in the treatment to a minimum, estimating with this App.
- This App can calculate these values together in three different conditions stated by three parameters (fraction dose or total dose, number of fractions and alpha/beta ratio), and summation of them automatically.
- Setting either a total dose or a fraction dose, related fraction dose or total dose is calculated respectively, depending on the fractionation times.
- This App (from ver.1.2.0) is just designed for iPhone and iPad with iOS8.

#Reference
1. J.F. Fowler, Review: Total doses in fractionated radiotherapy—Implications of new radiobiological data. Int J Radiat Oncol Biol Relat Studi Phys Chem Med 1984;46:103–120.
2. B. Emami, J. Lyman, A. Brown, et.al. Tolerance of normal tissue to therapeutic irradiation. Int J Radiat Oncol Biol Phys 1991;21:109–122. 
3. S.M. Bentzen, M.C. Joiner. The linear-quadratic approach in clinical practice. In M.C. Joiner, A. van der Kogel eds. Basic Clinical Radiobiology. 4 ed. London: Hodder Education; 2009: 120-134. 

#Disclaimer
- Please check carefully End User License Agreement (EULA) before using the App.
- Additionally, you may not use this App unless you agree to terms included below.
- You agree to assume full and sole responsibility for any use of this App.
- We are not responsible for any damages or injury, including but not limited to special or consequential damages, that result from your use of (or inability to use) this App, including any damages or injury caused by any failure of performance, error, omission, interruption, defect, delay in operation, computer virus, or other computer malfunction.

## Key features

- Calculate BED and EQD
- Adjust radiotherapy schedules
- Estimate treatment effects
- View alpha/beta ratio and tolerance dose tables
- Organize with URL scheme

## Recent user reviews (4 of 4)

All indexed reviews: https://appshunter.io/ios/app/eqd-calculator/id898546583/reviews.md

### 1/5 — Doesn’t work anymore

*2024-11-05*

Maybe it hasn’t kept up with the iOS updates , because it crashes as soon  as I open it now. Deleted and reinstalled, but that didn’t fix it.

### 5/5 — Update please!

*2024-01-27*

Please update this app I use it plenty in very upset it’s no longer working

### 5/5 — amazing app but crashes after ios17 update

*2023-11-28*

plz help. like someone else mentioned. this app i used all the time in clinic. thank u

### 5/5 — Best app ever until now

*2023-10-17*

Been using this app for years. But it no longer works after updating to iOS 17. It crashes all the time when I try to open it. 
Please help. 
Or if anyone could recommend some other apps with this nice tabular view that might as well work; it would be much appreciated.

## Frequently asked questions about EQD Calculator

### What is EQD Calculator used for?

EQD Calculator is used by radiation oncology professionals to easily calculate Biologically Effective Dose (BED) and Equivalent Dose (EQD) in radiotherapy practice. It helps in understanding and adjusting treatment plans.

### What devices does EQD Calculator support?

EQD Calculator is designed for iPhone, iPad, and iPod devices running iOS 8 or later. It was released on July 20, 2014, and last updated on March 26, 2015.

### How does EQD Calculator help with treatment changes?

The app can calculate the fraction dose equivalent to a specified number of fractionation times. This allows users to estimate the impact of changes in their radiotherapy schedule and minimize treatment effects.

### Can EQD Calculator calculate BED as well as EQD?

Yes, EQD Calculator can calculate Biologically Effective Dose (BED) defined by the Linear-Quadratic (LQ) model. It also simultaneously calculates the Equivalent Dose (EQD) for a specified fraction dose.

### Does EQD Calculator have ads?

No, EQD Calculator does not contain advertisements. It is a free application designed for professional use without any ad interruptions.

### What is the age rating for EQD Calculator?

EQD Calculator has an age rating of 17+. This is due to the professional and technical nature of the medical calculations it performs.

### Where can I find more information about the calculations used in EQD Calculator?

The app provides references to scientific papers on total doses in fractionated radiotherapy and tolerance of normal tissue to therapeutic irradiation. These are listed in the app's description for further study.

### What is the user rating for EQD Calculator?

EQD Calculator has a high user rating of 4.4 stars, based on 7 ratings. This indicates a positive reception from its users.

## Version history (last 5 releases)

### 2.3.0 — 2015-03-26

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

- “Contact Me” was prepared at the Information of the App.
- The issue with third-party custom keyboard fixed.

### 2.2.1 — 2015-01-30

- Slightly modification of internal cords.

### 2.1.1 — 2015-01-06

- Slightly modification of the keyboard.

### 2.1.0 — 2014-12-29

- Design of the keyboard was modified.
- Setting a total dose became capable.
- Slightly modification of view of reference data.
- Other minor problems were fixed.

### 1.2.0 — 2014-12-06

- The App became compatible with iPad (becomes Universal App).
- URL scheme (jp.37.EQDcalculator://) became capable to use.
- The development language of the App changed from Objective-C to Swift.
- From this version, the design of the App is just for iOS8, hence iOS7 or before was already incompatible.

## Apps similar to EQD Calculator

| App | Rating | Price | Category |
| --- | --- | --- | --- |
| [BED Calculator : Radiotherapy](https://appshunter.io/ios/app/bed-calculator-radiotherapy/id397088240) | 5.0 (3) | Free | Medical |
| [Ultrasound Touch](https://appshunter.io/ios/app/ultrasound-touch/id6472050218) | — | Free | Medical |
| [Multiplier](https://appshunter.io/ios/app/multiplier/id460335161) | 4.6 (23) | Free | Medical |
| [Easy Infusion Calculator](https://appshunter.io/ios/app/easy-infusion-calculator/id6740639804) | — | $2.99 | Medical |
| [iDCalc](https://appshunter.io/ios/app/idcalc/id556863722) | 5.0 (2) | $2.99 | Medical |
| [MediMorph](https://appshunter.io/ios/app/medimorph/id6479563936) | 5.0 (3) | Free | Medical |

## More apps by Hiroyuki KATOH

- [TDF Calculator](https://appshunter.io/ios/app/tdf-calculator/id900087159)
- [Calendar Calculator Free](https://appshunter.io/ios/app/calendar-calculator-free/id961898122)
- [Vertical Check Camera](https://appshunter.io/ios/app/vertical-check-camera/id967235607)
- [Musica Timer - Earphone Timer with Flexible Commands, Smart Input with a Numeric Keypad](https://appshunter.io/ios/app/musica-timer-earphone-timer-with-flexible-commands-smart-input-with-a-numeric-keypad/id983833338)

All apps by Hiroyuki KATOH: https://appshunter.io/developer/898546586

## Related topics

[eqd calculator](https://appshunter.io/ios/topics/eqd-calculator) · [tdf calc](https://appshunter.io/ios/topics/tdf-calc) · [radiation oncology](https://appshunter.io/ios/topics/radiation-oncology)

---

*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.*