Key
G - Gauge is the thickness of the body jewellery, the lower the gauge the thicker the jewellery.
L - Length is the inside length of the bar, this is between balls (or plate & ball in regards to labrets).
D - Diameter is the inside diameter of rings, horseshoes and other circular body jewellery.
Diameter (& Length) Converstions
(All sizes in millimetres have been rounded up or down.)
| Gauge |
Inches | Millimetres |
| 20G | _ | 0.8mm |
| 18G | _ | 1.0mm |
| 16G | _ | 1.2mm |
| 14G | _ | 1.6mm |
| 12G | _ | 2.0mm |
| 10G | _ | 2.4mm |
| 8G | _ | 3.0mm |
| 6G | _ | 4.0mm |
| 4G | _ | 5.0mm |
| 2G | 1/4" | 6.0mm |
| 0G | 5/16" | 8.0mm |
| 00G | 3/8" | 10.0mm |
| _ | 7/16" | 11.0mm |
| _ | 1/2" | 12.0mm |
| _ | 9/16" | 14.0mm |
| _ | 5/8" | 16.0mm |
| _ | 11/16" | 18.0mm |
| _ | 3/4" | 20.00mm |
| _ | 13/16" | 21.0mm |
| _ | 7/8" | 22.0mm |
| _ | 15/16" | 24.0mm |
| _ | 1" | 26.0mm |
| _ | 1 1/8" | 29.0mm |
| _ | 1 1/4" | 31.0mm |
| _ | 1 3/8" | 35.0mm |
| _ | 1 1/2" | 38.0mm |
| _ | 1 5/8" | 41.0mm |
| _ | 1 3/4" | 44.0mm |
| _ | 1 7/8" | 48.0mm |
| _ | 2" | 50.0mm |
Measuring CBRs (Captive Bead Rings)
The diameter is measured at the widest inside diameter. Gauge is measured on the widest point of the CBR. Ball size is measured on the widest diameter of the ball. Larger gauges of CBRs tend to have screw on balls (4G and above mostly) but all CBRs can have clip in (snap in) balls, which is more common.
Measuring Horseshoes (Circular Barbells)
The diameter is measured at the widest inside diameter. Gauge is measured on the widest point of the horseshoe. Ball size is measured on the widest diameter of the balls, normally both balls will be the same size. Up to 8G most circular barbells are externally threaded, 6G and above tend to be internally threaded.
Measuring Plugs, Tunnels etc...
These are measured by the outside diameter of the item, this is the G (gauge) of the item and relates to the thinkness of your piercing, e.g. if you have a 4G (5mm) hole in your ear then the G of the jewellery you should buy will be 4G (5mm). The length of these is measured between the front and back of the item, this is the part which will not be in your piercing and normally has a larger overall diameter to ensure that your jewellery doesn't fall out, this area of the item is called the wearable area of the item.
Measuring Straight Barbells
The gauge of these is measured at the thickest point of the barbell (shaft). The length is measured from between both balls. Up to 8G most barbells are externally threaded, 6G and above tend to be internally threaded.
Measuring Curved Barbells (Eyebrow Bars)
The gauge of these is measured at the thickest point of the barbell (shaft). The length is measured from between both balls, on the inside of the curved part of the barbell. Up to 8G most barbells are externally threaded, 6G and above tend to be internally threaded.
Measuring Labrets
The gauge of these is measured at the thickest point of the bar (stud). The length is measured from between the ball and the flat plate. (the flat plate part is worn inside the mouth and the ball is on the outside of the jewellery, most ball (or other attachments) are internally threaded, with the bar being externally threaded. (labrets which have internally threaded bars and externally threaded balls are generally more expensive).
Measuring Lip Loops
The gauge of these is measured at the thickest point of the bar (stud). The length is measured from between the ball and the begining of the curve (labelled A). The height is measured from the bar at the bottom (A) to the top of the curved top (height labelled B), this means that your piercing (hole) should be x (height of B) from the top of your lip, this should be kept in mind when buying these items.
