Both “inseam” and “outseam” are terms used to measure garments, especially pants or trousers. An inseam is a measurement of the inner pant leg, from the crotch to the hem of the pant. The outseam is a measurement of the outer pant leg, from the waistband to the hem of the pant.
A tailor uses these measurements to customize the fit and length of pants for consumers. Inseam measurements are usually found on clothing websites. Shoppers can determine if a pant is too long or too short before they make a purchase. For example, petite clothing is designed for women 4'11" to 5'4", misses clothing fits women who are 5'4" to 5'7", and tall clothing is for women 5'8" to 5'11". The different heights of women contribute to the different inseam and outseam selections necessary for women's clothing.
Today, the inseam does not necessarily go all the way to the bottom of the leg. There are numerous pant lengths, including full-length, ankle-length and cropped. Even within these groups, there are many variations on length. A full-length straight-leg pant does not measure up to a full-length flared pant. When making pants, a sample can be made out of muslin. This gives an idea as to the sizing, fit, and style before cutting and finishing the real project.