Jewelry Wire Gauge Chart

AWG is a geometric scale, not a lookup table: every gauge step multiplies the diameter by the 39th root of 92 (≈ 1.1229), and every three gauges roughly doubles or halves the cross-sectional area. The defining anchors are AWG 36 = 0.127 mm and AWG 0000 = 11.684 mm, giving the exact formula d(mm) = 0.127 × 92^((36 − AWG) / 39). The full reference table below is computed from that formula — it cannot drift out of date.

One trap for jewellers: gauge numbers are inverse. 20 gauge (0.81 mm) is thinner than 12 gauge (2.05 mm), and the steps are not even in millimetres — the jump from 20 to 18 gauge is 0.21 mm, while 8 to 6 is 0.85 mm. When a pattern says “20g jump rings” and your supplier lists millimetres, buy 0.8 mm, not 2.0 mm.

Ear wires: 20 or 21 gauge. Standard pierced-earring findings accept 18–22 gauge posts; 20g (0.81 mm) is the classic handmade ear wire — thin enough to pass comfortably, springy enough in half-hard wire to hold its shape. Jump rings: 16–18 gauge for bracelets and pendants that take a pull, 20–22 for delicate chains. Wrapping and weaving: 24–28 gauge — thin enough to coil tightly around a frame wire, thick enough not to snap under tension. Structural frames, bangles and ring shanks: 8–12 gauge, usually dead-soft then work-hardened.

Temper matters as much as gauge: the same 18g wire in dead-soft bends by hand, in half-hard springs back and holds. Buy half-hard for ear wires and jump rings, dead-soft for wrapping and forging.