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Comparative gauge chart

Body jewelry and needles tend to be identified by their gauge, using the Browne & Sharpe or American wire gauge system, at least in North America (many other regions simply use metric sizing). The larger the gauge, the smaller the diameter.


  1. Overview
  2. Common sizes
  3. Size equivalents


The diameter of an n gauge wire (commonly written "nga"), is defined to be:


For larger gauges written as m zeros, let n = −(m − 1). That is, 0ga = 0, 00ga = −1, etc.

Body jewelry is measured using calipers, Vernier Gauge, a micrometer or a gauge wheel by its outer diameter. Needles, in the medical sense (including play piercing needles), are measured by the inner diameter of the tube (so a 16ga needle will actually have an outer diameter of about 14ga), whereas piercing needles are always measured by their outer diameter. The body jewelry industry uses mostly even gauges between 18 and 00ga, although odd gauges are seen from time to time, usually when non-North American jewelry is being imported. The difference in diameter between gauges two units apart is about 26%. Larger sizes are usually referred to by their measured size.

Common sizes

Please note that some of the fractional sizes below have been rounded to their closest match:

Gauge Fractional size Inches Millimeters
1/32" 0.031" 0.794mm
18ga 0.040" 1.024mm
3/64" 0.047" 1.191mm
16ga 0.051" 1.291mm
14ga 1/16" 0.064" 1.628mm
12ga 5/64" 0.081" 2.053mm
3/32" 0.094" 2.381mm
10ga 1/10" 0.102" 2.588mm
8ga 1/8" 0.128" 3.264mm
5/32" 0.156" 3.969mm
6ga 0.162" 4.115mm
3/16" 0.178" 4.763mm
4ga 13/64" 0.204" 5.189mm
2ga 1/4" 0.258" 6.544mm
0ga 5/16" 0.325" 8.251mm
00ga 0.365" 9.266mm
3/8" 0.375" 9.525mm
000ga 0.410" 10.41mm
7/16" 0.438" 11.11mm
0000ga 15/32" 0.460" 11.68mm
1/2" 0.5" 12.7mm
00000ga 33/64" 0.517" 13.1mm
9/16" 0.563" 14.3mm
5/8" 0.625" 15.9mm
11/16" 0.688" 17.5mm
3/4" 0.75" 19.1mm
13/16" 0.813" 20.6mm
7/8" 0.875" 22.2mm
15/16" 0.9375" 23.8mm
1" 1.0" 25.4mm
1 1/16" 1.0625" 26.9875mm
1 1/8" 1.125" 28.575mm
1 3/16" 1.1875" 30.1625mm
1 1/4" 1.25" 31.75mm
1 5/16" 1.3125" 33.3375mm
1 3/8" 1.375" 34.925mm
1 7/16" 1.4375" 36.5125mm
1 1/2" 1.5" 38.1mm
1 9/16" 1.5625" 39.6875mm
1 5/8" 1.625" 41.275mm
1 3/4" 1.75" 44.45mm
1 7/8" 1.875" 47.625mm
2" 2" 50.8mm

Most body piercings are initially performed at between 14ga and 10ga depending on the piercing, but that is far from a hard rule and there are many arguments debating the subject of initial gauge size.

Gauge sizes do exist larger, but past 00ga people tend to use fractional imperial sizing (ie. "half inch").

Size equivalents

As far as the gauges of common household objects, below is a (vaugely accurate) list started by RAB's Lish:

Gauge Objects
16ga thumbtack tip, big safety pin.
14ga metal coat hanger, bike spoke, wire from triangular business clamp.
12ga wire hanger, spaghetti.
10ga round toothpick, q-tip shaft, small bamboo skewer.
8ga fire extinguisher pin, #5 crochet hook, lightsaber handles from Star Wars lego sets, small pilot lock, coffee swizzles, ink cartridge.
6ga juice box straw, lightbrite peg, mini-glowstick, Rold Gold pretzel stick, heroin-style medical tubing, round boot lace, lollipop stick.
4ga pilot stylus, large bamboo skewer, chopstick.
2ga drinking straw, power cord for N64, Bic automatic pencil, crayola colored pencil, yellow pipette tip, crossbow bolt, no.2 pencil.
0ga Bic round stic, candy cane, round chopsticks, Master Lock shackle, PCR tube, blue pipette tip, plastic clothes hanger.
00ga Bic round stic cap, 1/4" male headphone jack, lego person's head, fat crayons, American lock company #5200 shackle, beaded Christmas garland, Papermate Gel Roller pen.
000ga Sharpie marker body, wooden spoon handle, 1/4" female headphone jack, A/V adaptor plug head from Sony Playstation.
0000ga Sharpie marker cap, mini one-use hydrating shampoo/conditioner bottle, Eppendorf reaction vial