# Ethanol Calculator vs passwhistle

The clearest difference is price: passwhistle at Free against Ethanol Calculator's $9.99. Ethanol Calculator's advantage is update cadence (every 9 days vs every 2 months). On ads, in-app purchases, device support and iOS requirement there is nothing between them.

passwhistle is free to download; Ethanol Calculator costs $9.99 up front. Neither carries in-app purchases, so what you see is what you pay.

Ethanol Calculator ships an update every 9 days, passwhistle every 2 months. Both last shipped on October 24, 2026.

## The numbers

| Metric | Ethanol Calculator | passwhistle |
| --- | --- | --- |
| Price | $9.99 | **Free** |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | **Every 9 days** | Every 2 months |
| Size | 10 MB | 41 MB |
| Requires iOS | **16.0** | 16.4 |
| Devices | iPhone, iPad | iPhone, iPad |
| Age rating | 17+ | 4+ |
| Developer | [MOSTUNED LTD](https://appshunter.io/developer/6814598013) | [KAM INOVASYON BILISIM REKLAMCILIK A.S.](https://appshunter.io/developer/866563278) |

## What reviewers say

### Ethanol Calculator

[App page](https://appshunter.io/ios/app/ethanol-calculator-e85-fuel/id6757930343)

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

**In-app purchases:** none


### passwhistle

[App page](https://appshunter.io/ios/app/passwhistle/id6769729497)

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

**In-app purchases:** none


## Frequently asked questions

### Is Ethanol Calculator free?

Ethanol Calculator costs $9.99, with no in-app purchases.

### Is passwhistle free?

passwhistle is free to download, with no in-app purchases.

### Do Ethanol Calculator or passwhistle have ads?

Neither Ethanol Calculator nor passwhistle shows ads.

### Which is updated more often, Ethanol Calculator or passwhistle?

Ethanol Calculator ships an update every 9 days, and passwhistle every 2 months. Most recently, Ethanol Calculator was updated on October 24, 2026 and passwhistle on October 24, 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.*