Wheelbase is a term used to describe the distance between the centers of the front and rear wheels of a vehicle. It is an important measurement that affects a cars handling, ride, and interior space. The wheelbase is usually measured in millimeters or inches, depending on the region. In road and rail vehicles, the wheelbase is the horizontal distance between the centers of the front and rear wheels. For road vehicles with more than two axles, such as some trucks, the wheelbase is the distance between the steering (front) axle and the center point of the driving axle group. In skateboarding, the word "wheelbase" is used for the distance between the two inner pairs of mounting holes on the deck.

The wheelbase of a vehicle is related to the force on each pair of tires by the following formula: total torque of the forces acting on a vehicle is zero. Therefore, the wheelbase is an important factor to consider when choosing a car. A car with a long wheelbase will tend to have a more spacious interior than a car of the same length with a shorter wheelbase.

In summary, wheelbase is the distance between the centers of the front and rear wheels of a vehicle. It is an important measurement that affects a cars handling, ride, and interior space.