RC Speed Calculator Pro is a free iPhone utility tool developed by Degree3 Inc. It allows you to quickly and easily estimate your RC car's top speed. Simply input details about your gearing, motor, and batteries, and the app will calculate the rest.

You can save your estimates for comparison between different car setups and even record your actual top speed if you have a speed gun. The app requires information such as pinion gear teeth, battery cells or voltage, motor Kv rating, and tire diameter (which can be auto-filled based on your car type). Please keep in mind that the speed estimates provided are theoretical and may vary from real-world conditions.