What a body pillow is

A body pillow is any pillow long enough to support the trunk and a limb at the same time, which in practice means roughly from shoulder to knee.

How long is a body pillow?

The common US insert is 20 by 54 inches, long enough to run from the chest to the knees when you curl up.

The Mainstays insert at Walmart is a typical example (Walmart), and all five insert pages read for the main body pillow guide listed that size. Longer ones exist: one goose down and feather pillow is also sold at 20 by 72 inches (Walmart, Pillowtex). Before buying an unusual length, check that covers are sold for it.

Which shapes are there?

Straight, U, C or J, and wedge. The curved shapes are mostly sold as pregnancy pillows.

U shapes on the ten seller pages read for the U-shaped guide ran from 47 to 59 inches long, and a wide one runs 30 inches across (Regalo). Wedges are far smaller; one is listed at 15 by 13 by 4 inches (Dillard's). A pregnancy pillow is a body pillow in a curved shape, and every system that sorts products files both as bedding (what category is a body pillow).

How does the fill differ?

Polyester fiberfill is the usual default, shredded memory foam can be adjusted, and few pages say how much fill is inside.

Only one of five insert pages read for the main guide gave a fill weight: 38 ounces of polyester fiberfill (Walmart, Mainstays). Shredded foam pillows let you add or remove fill; Coop says its body pillows can be made soft and fluffy, or firm (Amazon, Coop Home Goods). Fill weight is the nearest thing a listing gives to how full the pillow is.