Ratio Calc! Apple

Ratio Calc!

By: David Mills App
Gearing for your R/C car

Overview

Apple Apps Store
Rating:
4.50
(25)
Version:
7.5.1
Last updated: 2025-11-11
Ranking
#228,633 ▼ 60
Overall

Features & Capabilities

Ratio Calc is a quick and easy tool for radio control car racers to use trackside. Knowing your final drive ratio (FDR) is very useful for comparison with other racers to determine if your car is geared correctly.

It lets you quickly select your car by filtering on manufacturer and model. Select your pinion and spur size and the FDR is displayed. Tyre diameter can also be entered to calculate your rollout.

Ratio and roll out charts are also available which plot pinion and spur gear combinations to create very handy reference tables.

  • Save your favourite cars for quick access

  • Select measurement units (imperial/metric)

  • Select your preferred gear pitch, alternative ratios in other pitches will be shown

  • Over 2000 cars/variants in the database which is updated regularly

User Growth & Download Statistics

App
By:
David Mills
Rating:
4.50
(25)
Version:
7.5.1 Last updated: 2025-11-11
Version code:
879565488
Creation date:
2011-05-12
Compatible devices:
Size:
46.38MB
Price:
2.99
URLs:
Website ,Privacy policy
Full description:
See detailed description
Source:
Apple Apps Store
Data ingested on:
2026-08-08
Compare stats and ranking:

Ranking

# 228,633 ▼ 60

For Developers

Monetize with App Pass Boost with Extension Booster

Contact the developer

Chrome-Stats does not own this Apple app. Please use these information below to contact the Apple app developer.
Developed by:
David Mills
Apple Apps Store
https://apps.apple.com/us/app/ratio-calc/id436311293
Website:
https://www.sllim-code.com

User Reviews

Ratio Calc! is highly praised for its large car library, fast gear ratio and rollout calculations, and easy-to-use interface. Reviewers value storing multiple cars, comparing final drive and rollouts, and its strong on-track usefulness. The main drawbacks cited are the desire for more frequent updates/new kits and the lack of per-car gear pitch settings. Overall, it’s regarded as a must-have tool for RC racers with room for feature enhancements.
Pros
  • Large car library with easy addition of new cars
  • Fast, accurate gear ratio and rollout calculations
  • Easy to use with a clean, intuitive UI
  • Stores multiple cars and allows quick comparisons of final drive ratios and rollouts
  • On-track usefulness and updates add new cars quickly
Cons
  • Requests for more frequent updates and inclusion of new kits
  • Lacks per-car gear pitch settings; gear pitch cannot be set for each car
Recent reviews
Keep it up !!!!!! Your last updated totally made my day.
by Wr*****, 2024-12-08
I have the app for iphone but I've recently switched to android and would love to use this on my new phone for my rc racing.
by kf*****, 2024-02-21
View all user reviews ›

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