The time it takes to accelerate from 0 to 60 mph is a commonly used performance measure for automotive acceleration in the United States and the United Kingdom. In the rest of the world, 0 to 100km/h is used. Present performance cars are capable of going from 0 to 60 mph in under 6 seconds, while exotic cars can do 0 to 60 mph in between 2 and 3 seconds, whereas motorcycles have been able to achieve these figures with sub-500cc since the 1990s. The fastest automobile in 2015 was the Porsche 918 Spyder, which is a hybrid vehicle taking 2.2 seconds to accelerate from 0 to 60 mph. Measuring the 0 to 60 mph speed of vehicles is usually done in a closed setting such as a race car track or closed lot used for professional drivers. This is done to reduce risk to the drivers, their teams, and the public. The closed course is set up for test-drives in order to reduce any variables, such as wind, weather, and traction. Each variable can have a dramatic impact on the friction of the track and the drag placed on the vehicle, which will influence the overall 0 to 60 time that is recorded. The crew sets up accurate and precise measuring tools that are attached to computers. These tools included Doppler radar guns and precise timing instruments that are synchronized. This means that the driver is not worried about keeping time or the exact moment the car hits 60miles per hour. The driver focuses solely on driving straight and fast with professional quick gear shifting. The car is timed and recorded going in two separate and opposite directions. This practice eliminates variables such as wind, directional traction of the track and driver performance. The two times are averaged together to achieve the commonly accepted 0 to 60 time. Jalopnik has said that launch control systems appearing on production exotic cars in the 2010s have made published 0 to 60 times invalid, since these cars have slower times from 5 mph to 60 mph. Most car magazines and manufacturers in the United States use a rolling start allowance term "1-foot rollout", which means that the timer is only started once the car has traveled, reducing the measured time by up to 0.3 seconds.
