This tool converts rotational speed, measured in **revolutions per minute** **(RPM)**, to linear speed, expressed in **miles per hour (mph)**.

Enter

- Either diameter or circumference
- RPM

🔁 mph to RPM

**Formula**

To convert from revolutions per minute (**RPM**) to miles per hour (**mph**), you need to know the diameter **d** of the circle the point is traveling around. The circumference **C** of a circle is calculated by:

**C = π × d **

where:

**π**is approximately 3.14159,**d**is the diameter of the circle.

The conversion from RPM to miles per hour can be done with the following formula:

**Miles Per Hour = RPM × π × d** **×** **0.03728**

Here’s how it works:

**RPM**is the rotational speed you want to convert.**π×d**gives the circumference in meters.**0.03728**converts to Miles per hour

**Example Calculations**

Consider a wheel with a diameter of 0.5 meter. If this wheel rotates at a speed of 1000 RPM the linear speed of a point on the circumference of the wheel is approximately 58.56 Miles per hour.

**Background**

**Rotational Speed** refers to the number of complete turns a rotating object makes per unit of time. It is commonly measured in revolutions per minute (RPM), indicating how many full rotations occur in one minute. This measurement is critical in understanding the dynamics of rotating machinery, such as engines, turbines, and wheels.

**Linear Speed** is the distance traveled by a point on the circumference of the rotating object along its path in a given period of time, measured in miles per hour (m/s). Converting RPM to MPH helps in understanding the relationship between the rotational motion of an object and its linear motion.