At which altitude does an aircraft typically cruise?

Aircraft typically cruise at altitudes that range between 30,000 to 40,000 feet, with 35,000 feet being a common cruising altitude. At this altitude, the aircraft can take advantage of smoother air, which is beneficial for fuel efficiency and passenger comfort. The higher altitude minimizes turbulence from ground-level weather patterns and allows the aircraft to fly above most commercial air traffic.

Flying at this altitude also provides optimal operating conditions for jet engines, as the thinner air reduces drag and enhances fuel consumption efficiency. As a result, cruising at 35,000 feet represents a compromise between performance, safety, and passenger experience for airlines.

While there are lower cruising altitudes, such as 10,000 and 20,000 feet, these are generally used during ascent or descent, and are not typical for sustained levels of cruising, especially for longer flights.