Thing is, at altitudes from sea level to perhaps 25,000 feet above sea level (abbreviated MSL standing for Mean Sea Level) the modern turbo-jet powered aircraft can climb at rates approaching 5,000 feet per minute. They usually don't because of a number of reasons.
However, above that altitude, the density of the air reduces dramatically and the rate of climbs reduces similarly. Most older turbojets, such as the earlier models of the Boeing 737, all models of the Boeing 727 and the ancient, but still in service McDonnell Douglas DC-9's don't perform as well as the newer generations due to aerodynamic and engine improvements.
Additionally, Air Traffic Control (ATC) procedures slow down the climbs for traffic separation (a good thing, no?)
But for an example, ( have been a commercial airline pilot most of my adult life) I was in command of a DC-9-81 coming out of Zihuatanejo, Mexico late one night. We had experienced a mechanical problem earlier in the day and after out mechanics worked on it the decision was made to bring the aircraft back to a manintenance base in the States for further work. That type of a flight, with required crew only, no passengers, is called a ferry flight.
We had unlimited airspace and climbed from sea level to 35,000 feet in less than 10 minutes. Had the same flight been conducted with passengers it would have taken nearly 30 minutes.
Most passengers are very uncomfortable with sustained flight at the high deck angles that produce those kinds of climb rates. As an aside, an F-16, F-18 or other fighter jet can climb vertically at rates nearing 15,000 feet per minute. Problem is that at the required power setting including full afert-burner, the fuel used in such a climb almost exhausts the total fuel supply on board the aircraft...