# Racing Diffs vs Tire Sizes

The clearest difference is rating: Tire Sizes at 4.5 against Racing Diffs's 2.5. Tire Sizes also leads on ratings volume (82 vs 2). Racing Diffs's advantage is in-app purchases (none vs 1) and iOS requirement (14.4 vs 17.0). On price, update cadence, ads and monetization model there is nothing between them.

Both are free to download. Tire Sizes sells 1 one-off in-app purchase. Racing Diffs asks for nothing beyond the download.

Tire Sizes holds the better App Store score, 4.5 against 2.5. That said, the two scores are not equally well evidenced: Tire Sizes has 82 ratings behind it against 2, so its average is the more settled of the two.

Racing Diffs ships an update every 5 weeks, Tire Sizes every 6 weeks. The most recent releases landed on November 3, 2026 and October 30, 2026 respectively.

## The numbers

| Metric | Racing Diffs | Tire Sizes |
| --- | --- | --- |
| Price | Free | Free |
| Rating | [2.5 (2 ratings)](https://appshunter.io/ios/app/racing-diffs-gear-ratio/id1554897307/reviews) | **[4.5 (82 ratings)](https://appshunter.io/ios/app/tire-sizes/id6743722834/reviews)** |
| Number of ratings | 2 | **82** |
| Positive reviews | — | 0.0% of reviews |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | **Every 5 weeks** | Every 6 weeks |
| Monetization | Free | Free |
| Size | 6 MB | 17 MB |
| Requires iOS | **14.4** | 17.0 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [Imperio](https://appshunter.io/developer/521569345) | [Zaven Hovhannisyan](https://appshunter.io/developer/1804196073) |

## What reviewers say

### Racing Diffs

[App page](https://appshunter.io/ios/app/racing-diffs-gear-ratio/id1554897307)

Calculate your vehicle's top speed for each gear using transmission ratios, differential gear ratio, and rev limit. Optimize your car's gear ratio for track performance or drag racing, choosing between kmh and mph units.

**Highlights:** Top speed calculation per gear, Input tire dimensions, Input transmission gear ratios, Input final drive ratio, Input rev limit, Supports kmh and mph

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

**In-app purchases:** none


### Tire Sizes

[App page](https://appshunter.io/ios/app/tire-sizes/id6743722834)

Find essential tire dimensions and receive suggestions for new tire sizes. Compare wheels visually and by specifications like offset and width. Discover factory tire sizes for your car and compare motorcycle tires across different measurement systems.

**Highlights:** Tire dimension calculations, New tire size suggestions, Wheel comparison (visual and specs), Offset and width comparison, Motorcycle tire comparison, Factory tire size lookup

**Features:** macOS Compatibility

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Remove Ads | $3.99 | one-time |


## Frequently asked questions

### Is Racing Diffs free?

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

### Is Tire Sizes free?

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

### Which has better reviews, Racing Diffs or Tire Sizes?

Tire Sizes is rated higher. Racing Diffs averages 2.5 out of 5 from 2 ratings, while Tire Sizes averages 4.5 from 82 ratings.

### Do Racing Diffs or Tire Sizes have ads?

Neither Racing Diffs nor Tire Sizes shows ads.

### Which is updated more often, Racing Diffs or Tire Sizes?

Racing Diffs ships an update every 5 weeks, and Tire Sizes every 6 weeks. Most recently, Racing Diffs was updated on November 3, 2026 and Tire Sizes on October 30, 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.*