BELLY RING SIZING INFORMATION: Most belly button piercings are done with a 14 gauge 1/2 inch (12mm-that is on the longer side) to compensate for swelling after piercing. When the piercing heals, most people can use a shorter barbell in 1/4 inch (6mm-for very shallow piercings), 5/16 inch (8mm) or 3/8 inch (10mm) length, but not everyone! Again, this is a guideline. If your piercing is shallow, you may need a shorter length barbell 1/4 inch (6mm). Deeper navel piercings may need a 7/16 inch (11mm), 1/2 inch (12mm), 9/16 inch (14mm). We even carry belly button rings with a long 5/8 inch (16mm) barbell. Many years ago piercers were using 16 gauge (which is slightly thinner than 14 gauge) so if your piercing is older, you may have a 16 gauge piercing. The only way to properly determine the size you need is to measure or consult your piercing professional.
We have more information on how to measure your belly ring size- Belly Ring Sizing Chart