Wire gauge is the small thing that trips up every beginner. The numbers run backwards — a higher gauge number means thinner wire — and the UK/US (AWG) and metric systems don't agree with each other. Buy "20 gauge" without checking which system, and you can be 0.1 mm out, which is the difference between an ear wire that holds its shape and one that bends in the box. Get gauge right and half of your fit and strength problems disappear before you've made a single cut.
The conversions worth memorising
In AWG (American Wire Gauge, the most common standard for jewellery wire): 26g ≈ 0.40 mm, 24g ≈ 0.51 mm, 22g ≈ 0.64 mm, 20g ≈ 0.81 mm, 18g ≈ 1.02 mm, 16g ≈ 1.29 mm, and 14g ≈ 1.63 mm. When a UK supplier lists wire in millimetres, they're giving you the honest number — no conversion needed. If you're ever unsure which system a coil uses, don't guess: measure it. A sliding gauge settles the argument in seconds and saves a ruined batch.
Which gauge for which job
- 26–24g (0.4–0.5 mm): wrapping, weaving, and binding wire for holding parts together while soldering.
- 22–20g (0.6–0.8 mm): ear wires, light jump rings, headpins and delicate links.
- 18–16g (1.0–1.3 mm): sturdy jump rings, clasps and frames — the everyday workhorse range most makers reach for.
- 14g and thicker (1.6 mm+): ring shanks, bangles and structural work that has to take real load.
For coiling and looping you'll want a few mandrels in graduated sizes — a mini oval mandrel set covers most jump-ring and bail diameters in one case.
Temper matters as much as thickness
Wire is sold in tempers — soft, half-hard and hard. Soft bends easily and is ideal for wrapping and forming; half-hard holds a shape better and suits ear wires and clasps; hard resists bending and suits findings that must stay rigid under load. Working the wire hardens it as you go, which is why a soft wire stiffens noticeably after a few bends in the same spot. When it gets too stiff to work safely, anneal it back to soft — the same softening cycle covered in our forming guides — and it'll behave like new.
Cutting it cleanly
The thicker the wire, the more your cutters matter. Soft 22g shears with almost anything, but 16g and up needs a proper flush cutter to leave a clean, pinch-free end: our tungsten-carbide side cutters take wire up to 12g, while slim-line side cutters suit fine and confined work. Memory-steel and hardened wire will chip a standard cutter — see cutting hardened jewellery wire for the right approach. Once you're cutting consistent lengths, making your own jump rings becomes the obvious next step.
Find cutters and pliers in the Pliers & Cutters range, and forming mandrels under Mandrels & Sizing.