# e-calcFree

> Scientific calculator with engineering notation, history, and formula editing. (iPhone/iPad app by e-skett Corp..)

- Source: https://appshunter.io/ios/app/e-calcfree/id591591892 (this page in markdown: same URL + `.md`)
- Developer: [e-skett Corp.](https://appshunter.io/developer/591591895)
- Category: Productivity, Utilities
- Price: Free
- Rating: 3.00/5 from 1 App Store ratings · 9 written reviews indexed
- Age rating: 4+
- Requires: iOS 6.1 · 7 MB
- Languages: American English, Japanese
- Released: 2013-01-12
- Data updated: 2026-08-22
- Monetization: free
- User reviews in markdown: https://appshunter.io/ios/app/e-calcfree/id591591892/reviews.md

## What is e?

This calculator can be used not only in scientific notation(e.g. 1E-6) but also using engineering multipliers(e.g. p,n,u,m,k,M).
By pressing the [ENG] button, the display of calculation result will change. (e.g. 1E-9 or 1n)
Calculation results in the past is displayed in the history area.
When you tap the formula  area , you will be able to edit it. You will be able to re-calculate.
Unit that can be entered from the button is p = 1E-12, n = 1E-9, u = 1E-6, m = 1E-3, k = 1E3, M = 1E6. (f = 1E-15 and G = 1E9 is used for display only）.
iPhone4 can display four lines in history area. iPhone5 can display 9 lines. 
The main limitations of Free version is as follows.
you can not scroll history area.
History is not saved when you exit.

## Key features

- Scientific notation support
- Engineering multipliers (p, n, u, m, k, M)
- History of past calculations
- Editable formulas for recalculation
- Unit conversion for engineering prefixes

## Recent user reviews (9 of 9)

All indexed reviews: https://appshunter.io/ios/app/e-calcfree/id591591892/reviews.md

### 4/5 — ギガと光速が欲しい

*2021-06-21*

変な広告もなく使いやすいのは良いが、無線屋さんにとっては単位系にG(10^9)が無いと使いにくい。また、定数に光速cがあると、波長計算とかが楽なのですが…

### 1/5 — No support

*2021-06-14*

Having trouble entering scientific notation numbers into the app with no luck. Tried contacting the creator for support but everything is in Chinese making it impossible.

### 5/5 — 補助単位 k、m、Mが使えるのが助かります

*2019-09-25*

エンジニアです。

設計計算する際、
補助単位k、m、Mなどをよく使います。

手元の関数電卓も補助単位が入力できるものを使っていましたが、
スマホのアプリの関数電卓にそのような機能がなく不便でした。

このアプリは補助単位が使え、とても重宝します。

工学系エンジニアにはオススメのアプリです！

### 1/5 — Piece of junk!

*2015-05-11*

I'm learning about scientific notation in school. We were assigned homework and I was looking forward to a quick finish but still correct answers. The default calculator lacked scientific notation so I got a new one. That calculator lasted 8 minutes on my phone. My opinion; save your time and don't get this. This calculator made no sense. I went to help and found nothing AT ALL on scientific notation. In conclusion, piece of junk! (I gave it a star at all because I couldn't send this without a rating).

### 2/5 — もう一歩

*2013-06-29*

p,n,uの表示ができるのは★5
ただエンジニア向けのアプリのことだが
1/3=0.3333333
ANS*3=0.999999
となることと
16進などが扱えないので★2個
今後に期待します

### 4/5 — とても良い

*2013-06-17*

電気エンジニアが良く使う単位で計算できるのが素晴らしい！
ボタンが小さく押しづらいので星一つ下げました(._.)

### 3/5 — フリーアプリだからか

*2013-05-23*

一定時間触らずにENG?をタップすると落ちる。これではせっかくの履歴機能も無駄になってしまう。
所詮フリーアプリといったところか

### 5/5 — Great app!

*2013-03-17*

The engineering prefixes are fantastic!!

### 5/5 — 指数単位がとても便利

*2013-02-01*

有料版で構わないので、自然対数や、eをはじめ、μ0などの各種定数もサポートして欲しいです。メガやキロ、マイクロなどはとても便利です。

## Frequently asked questions about e

### What are the main limitations of e-calcFree?

The free version of e-calcFree does not allow scrolling through the history area. Additionally, calculation history is not saved when you exit the application.

### Does e-calcFree support engineering multipliers?

Yes, e-calcFree supports engineering multipliers such as p (1E-12), n (1E-9), u (1E-6), m (1E-3), k (1E3), and M (1E6). The display can also show f (1E-15) and G (1E9).

### Can I edit previous calculations in e-calcFree?

Yes, you can tap the formula area to edit a previous calculation. This allows you to re-calculate with modified inputs.

### What devices is e-calcFree compatible with?

e-calcFree is compatible with iPhone, iPad, and iPod devices. It was released on January 12, 2013, with the latest version being 1.23 updated on November 5, 2015.

### What is the age rating for e-calcFree?

e-calcFree has an age rating of 4+, making it suitable for a wide range of users.

### How often is e-calcFree updated?

The application was last updated on November 5, 2015, to version 1.23. This indicates a less frequent update cycle.

### What is the user rating for e-calcFree?

e-calcFree has a rating of 3.0 stars based on 1 rating. This suggests limited user feedback is available.

### Does e-calcFree have ads?

No, e-calcFree does not contain advertisements. It is a completely free application without any ads.

## Version history (last 5 releases)

### 1.23 — 2015-11-05

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

- When you press the 'x' or '/' after pressing  '='  automatically "()" is inserted.

### 1.22 — 2014-11-08

Fixed bug in iOS8

### 1.21 — 2014-01-07

Minor bug fixes "Del" button

### 1.20 — 2013-09-18

iOS7 fixes
Change 2xpi_ to (2xpi_)

### 1.11 — 2013-04-10

*Constant calculation bug fixes.

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## More apps by e-skett Corp.

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All apps by e-skett Corp.: https://appshunter.io/developer/591591895

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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 2026-08-22.*