For every body or facial piercing, there is a set of common sizes that the majority of persons will be pierced at. Knowing these sizes won’t be a fail safe, but it can help tremendously when buying body jewelry. Here they are:
20 Gauge: This is the smallest gauge that regular body jewelry will come in, and is used almost exclusively for nose piercings. Some people who had their piercing performed in India, the Middle East, or very select areas of the US, UK, Australia, or Europe may require an even tinier 22 gauge, which would normally be considered a specialty size, and may need to be handmade by an artisan.
18 Gauge: This is the gauge used for larger sized nose piercings, some single piercings of the ear cartilage, standard ear lobe piercings, and very occasionally for piercings of the lip (mostly on females.) Slightly larger than a 20 gauge, you’ll normally find small studs, regular pierced earrings, nose rings, and circular jewelry like BCRs in this size.
16 Gauge: Piercings performed in a 16 gauge vary widely, and will include various piercings of the ear, the septum, the facial area around the mouth (labrets, monroes, medusas, etc.), the eyebrow, and infrequently possibly even the belly button, eye lid, nostril, or some surface piercings. Due to its variability, you’ll find sixteen gauge jewelry in circulars, straight barbells, curved barbells, studs, and various retainers.
14 Gauge: The 14 gauge size is even more versatile than the 16, including the vast majority of belly piercings, tongue piercings, nipple piercings, surface piercings, and many of the lip piercings, like the labret. Piercings of the septum, ear cartilage, eyebrow, and upper lip may also be made in a 14 gauge. Thus the jewelry will usually be found in almost all types ranging from circular, to spiral, barbell, shield, stud, spike, retainer, and even small plugs or eyelets.
12 Gauge: Although a 12 gauge isn’t generally the standard, piercings of the ears, lip, or septum in particular may be done in this larger gauge, especially those piercings on men that would generally be worn slightly smaller on a woman. Also, because the sizing difference is easily overcome, many who are in the beginning stages of stretching a piercing of the nose, lip, or ear may require this gauge, which can be readily found in barbells, circulars, and plugs.
Most gauges larger than a 12 will be found in circulars, straight barbells, and plugs or tunnels only, as these larger gauges require a piercing to be stretched in order to accommodate them.