# simpleFIRE vs DieselCalcs

The clearest difference is update cadence: simpleFIRE at every 6 days against DieselCalcs's every 2 months. simpleFIRE also leads on iOS requirement (16.0 vs 18.4). DieselCalcs's advantage is monetization model (free vs free with in-app purchases) and ratings volume (3 vs 1). On price, rating, ads and in-app purchases there is nothing between them.

Both are free to download. simpleFIRE sells 1 one-off in-app purchase and DieselCalcs sells 3 one-off in-app purchases. Whichever you choose, the download price is not the number that matters.

On the App Store both sit at effectively the same score — 5.0 for simpleFIRE against 5.0 for DieselCalcs. Both are backed by a comparable volume of ratings — 1 and 3 respectively.

simpleFIRE ships an update every 6 days, DieselCalcs every 2 months. The most recent releases landed on October 24, 2026 and October 22, 2026 respectively.

## The numbers

| Metric | simpleFIRE | DieselCalcs |
| --- | --- | --- |
| Price | Free | Free |
| Rating | [5.0 (1 ratings)](https://appshunter.io/ios/app/simplefire-fire-calculator/id6504460384/reviews) | [5.0 (3 ratings)](https://appshunter.io/ios/app/dieselcalcs/id6753960100/reviews) |
| Number of ratings | 1 | **3** |
| In-app purchases | Yes | Yes |
| Ads | No | No |
| Update frequency | **Every 6 days** | Every 2 months |
| Monetization | Free with in-app purchases | **Free** |
| Size | 3 MB | 6 MB |
| Requires iOS | **16.0** | 18.4 |
| Devices | iPhone, iPad | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [DAWID MICHAL MILCZAREK](https://appshunter.io/developer/1752376249) | [Drew Sullivan](https://appshunter.io/developer/1845947341) |

## What reviewers say

### simpleFIRE

[App page](https://appshunter.io/ios/app/simplefire-fire-calculator/id6504460384)

Effortlessly plan your financial future with intuitive sliders and advanced settings. This ad-free calculator keeps your data private and secure on your device, offering a one-time purchase for lifetime access to all features.

**Highlights:** Intuitive sliders for financial input, Compound interest calculation, Advanced settings (withdrawal rates, inflation), Ad-free experience, One-time payment for lifetime access, Privacy-focused, no data collection

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

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| simpleFIRE Premium | $24.99 | one-time |


### DieselCalcs

[App page](https://appshunter.io/ios/app/dieselcalcs/id6753960100)

This app offers a suite of financial calculators designed to help users achieve financial independence. It provides tools for retirement planning, investment growth, and major purchase analysis, all with a focus on user privacy and a free, ad-free experience.

**Highlights:** FIRE Calculator (Traditional, Coast FI, Monte Carlo), Buy vs Rent analysis, Compound Interest calculator modes, Car Payment calculator, Inflation adjustment calculator, Privacy-first, on-device calculations, Ad-free and free to use

**Features:** macOS Compatibility

**In-app purchases (3)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Small Matcha | $0.99 | one-time |
| Medium Matcha | $2.99 | one-time |
| Large Matcha | $4.99 | one-time |


## Frequently asked questions

### Is simpleFIRE free?

simpleFIRE is free to download, with in-app purchases available.

### Is DieselCalcs free?

DieselCalcs is free to download, with in-app purchases available.

### Which has better reviews, simpleFIRE or DieselCalcs?

simpleFIRE and DieselCalcs are both rated 5.0 out of 5 on the App Store, from 1 and 3 ratings respectively.

### Do simpleFIRE or DieselCalcs have ads?

Neither simpleFIRE nor DieselCalcs shows ads.

### Which is updated more often, simpleFIRE or DieselCalcs?

simpleFIRE ships an update every 6 days, and DieselCalcs every 2 months. Most recently, simpleFIRE was updated on October 24, 2026 and DieselCalcs on October 22, 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.*