Airplane seat pitch has decreased over the last few decades from about 34 inches (around 86 cm) to just 31 inches (less than 79cm). Pitch is a measurement of one point on a seat to that exact same point on the seat in front of (or behind) it. Airlines have defended the decrease in pitch distance by stating that seat padding technology has improved to take up less space, so they claim legroom has not changed. Lack of legroom remains one of the biggest complaints among fliers, however, especially on flights over six hours in length. Fortunately, some airlines have started ordering planes with an extra inch (about 2.5 cm) of pitch, which is welcome news for most travelers.
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On flights under six hours in duration, comfort is the fifth highest concern for airline customers; for flights over six hours, however, it is the second highest concern — after sufficient legroom.
While legroom is a concern, seat width is also a major issue. Seats are measured using people’s hips, even though elbow room requires much greater width.
Airplane manufacturers often suggest a seat pitch of 34 inches (about 86 cm), but the airlines ultimately decide on what distance they want when they order planes.