Piercing Jewellery Measurements: Millimetres and Gauge

Millimetres and Gauge are encountered in piercing studios in catalogues and conversations with suppliers. To ensure an order is clear, it must first be clear which dimension is being referred to: bar thickness, wearable length, inner ring diameter or the size of a decorative end. These measurements are not interchangeable.

Millimetres: the direct measurement

The millimetre is a metric unit of length. When referring to piercing jewellery, a mm measurement can denote different dimensions:

• Bar thickness: the diameter of the bar;
• Wearable length: the length of the bar between the ends, which sits in the tissue;
• Inner ring diameter: the distance across the inside of the ring;
• Decorative end measurement: for example, the width of a visible decorative piece.

Therefore, note not only a number, but also what it refers to. "1.2 mm" without a dimension can be ambiguous in an order.

What Gauge Means

The Association of Professional Piercers uses Gauge as a designation for the thickness of a piercing jewellery bar. As several Gauge systems exist, do not infer a millimetre measurement from the designation alone. For a specific order, follow the manufacturer's product specification and confirm which dimension it describes.

Electrical AWG tables are not piercing jewellery tables. AWG stands for American Wire Gauge and describes wire diameter. Such a table must not be applied to body piercing jewellery without verification.

How to Avoid Ordering Mistakes

1. Fully name the dimension: thickness, wearable length, inner diameter or decorative end size.
2. Use the manufacturer's mm measurement together with their Gauge designation where possible.
3. Check the specific product illustration and order variant before transferring measurements into your inventory system.
4. If two measurements do not match, ask the manufacturer, rather than rounding a number yourself.
5. When changing jewellery, the size must match the placement and individual anatomy.

For workshop measurements, use an appropriate, intact measuring tool. A rough measurement does not replace the manufacturer's specification when it comes to the compatibility of a specific system.

Conclusion

Gauge is a useful catalogue designation, but it does not identify the measured dimension by itself. For every order, state whether the measurement is thickness, wearable length or diameter, then confirm the millimetre value in the product information.

Professional Sources

• Association of Professional Piercers: Jewelry for Initial Piercings
• Brady: American Wire Gauge sizes and diameters – this source describes AWG for wires, not piercing jewellery.