How to Measure Body Jewelry

Gauge, diameter, length — every jewelry type explained with diagrams. Know exactly what you need before you walk in.

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Gauge Quick Reference

Higher number = thinner. This trips up a lot of people.

GaugeDiameter (mm)Common For
22G0.6mmVery fine nose piercings
20G0.8mmNostril, eyebrow, some ear piercings
18G1.0mmNostril, helix, flat, tragus, septum
16G1.2mmCartilage, daith, rook, conch, lip
14G1.6mmNavel, nipple, tongue, industrial
12G2.0mmStretched earlobes, large gauge
10G2.4mmStretched lobes
8G3.2mmStretched lobes

Jewelry Types — How Each Is Measured

INNER DIAMETER
Captive Bead Ring (CBR)
Measure: Inner Diameter

Measured in a straight line across the center of the ring, from the inside edge to inside edge. The bead/ball is not included in the measurement.

Common sizes: 6mm · 8mm · 10mm · 12mm · 14mm
💡 Most ear and nose piercings use 6–8mm. Septum and navel tend to use 8–10mm.
INNER DIAMETER
Circular / Horseshoe Barbell
Measure: Inner Diameter

Same as a CBR — measured straight across the inside of the curve. The balls at each open end are not counted in the diameter.

Common sizes: 8mm · 10mm · 12mm
💡 Septum piercings commonly use 8mm. Industrial/daith often 10–12mm.
LENGTH
Labret / Flat Back Stud
Measure: Shaft Length

Measured from the top of the flat back disc to the bottom of the decorative top. Does not include the disc thickness itself.

Common sizes: 5mm · 6mm · 8mm · 10mm
💡 Initial piercings use longer bars (8–10mm) for swelling. Downsizing to 5–6mm once healed.
LENGTH
Straight Barbell
Measure: Length (end to end)

Measured in a straight line from the outside of one ball end to the outside of the other. Both ball ends are included.

Common sizes: 10mm · 12mm · 14mm · 16mm
💡 Tongue piercings initially use 16mm to allow swelling, then downsize to 12mm.
LENGTH(straight line)
Curved Barbell (Banana)
Measure: Length (straight line)

Even though the bar is curved, length is measured as a straight line between the two ball ends — not along the curve of the bar.

Common sizes: 8mm · 10mm · 12mm · 14mm
💡 Navel piercings typically use 10–12mm. Daith often uses 8–10mm.
GTHICKNESS OF POST
Gauge (Thickness)
Measure: Thickness of the post

Gauge measures how thick the post/bar is. Counterintuitively, the higher the gauge number, the thinner the jewelry. 20G is thinner than 14G.

Common sizes: 20G (0.8mm) · 18G (1.0mm) · 16G (1.2mm) · 14G (1.6mm)
💡 Most nostril piercings are 18G. Most ear cartilage is 16G. Nipple/navel are typically 14G.
LENGTHball to bend
Nose Screw
Measure: From ball to bend

Measured on the inside of the screw — from the end of the decorative ball down to where the wire begins to curve/bend.

Common sizes: 6mm · 7mm · 8mm
💡 Most nostril piercings use 6–7mm nose screws. Longer = more likely to show inside nostril.
LENGTHbump to ball
Nose Bone
Measure: From bump to ball

Measured from the small bump at the bottom (the anchor that holds it in) straight up to the end of the decorative top ball.

Common sizes: 6mm · 7mm · 8mm
💡 The bump makes it harder to insert/remove — not recommended for healing piercings. Best for healed nostrils.

Pro Tips Before You Buy

  • Don't guess. Bring your old jewelry in and we'll measure it. Trying to eyeball gauge or diameter almost always ends in the wrong purchase.
  • Threadless tops are brand-specific. A BVLA top won't always seat correctly on a NeoMetal post. Buy matching brands or have your piercer check compatibility.
  • Healing piercings need longer bars. Your initial jewelry is intentionally longer than what you'll end up with — that extra length is for swelling. Don't swap it out early.
  • Downsize before upgrading. Get your downsize first, confirm the sizing, then go shopping for fancy tops. It's heartbreaking to buy a $90 BVLA piece before knowing your correct gauge.
  • Implant-grade matters. Don't put mystery metal in a healing piercing just because it's the right size. Gauge and material are both important.

Not sure what size you need?

Come in and we'll measure you. Free. Takes two minutes. Walk-ins welcome.

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