According to National Workwear, Inc, a 29-inch waist is approximately equal to a women's size 6, a a girl's size 16 and a junior's size 9. For boys, a 29-inch waist is approximately equal to a size 18 regular and a size 14 husky.
Because sizing varies based on a variety of factors including brand, cut and style, it is a good idea for both men and women to try on pants or shorts before purchasing them. A woman with a 29-inch waist might fit into a women's size 16 in one pair of pants and a women's size 20 in another. The same is true for men's pants, though less variation in cut and style is common.