The Gauge System, Explained
Higher number, thinner post. That's the whole confusing part. A 20g post is thinner than an 18g, which is thinner than a 16g. Once that clicks, the rest of this is easy.
Quick conversions: 20g = 0.81mm 18g = 1mm 16g = 1.2mm 14g = 1.6mm
What's Standard for Lobes
20g is what you'll typically get from a mall kiosk piercing gun. Most professional studios default to 18g or 16g instead for a fresh lobe piercing, since a slightly thicker post tends to sit more securely and hold up better long term.
What's Standard for Cartilage
16g is the go-to for helix, tragus, conch, and most other cartilage spots. Thinner gauges can actually work against you here, cartilage tends to heal better and hold jewelry more securely with a bit more thickness to work with, not less.
Gauge and Length Are Different Numbers
We covered this in our post sizing guide, but it's worth repeating: gauge is thickness, length is how long the post is. You need both correct, and they're independent of each other. Don't assume one tells you the other.
One Thing to Know About Threadless
If you're planning to wear threadless jewelry, gauge matters even more. Threadless flat backs typically max out around 12g, so if your piercing runs thicker than that, you'll be looking at internally threaded jewelry instead.
How to Actually Find Your Gauge
Ask your piercer, they'll know exactly what you were pierced with. If you're shopping without that information, don't guess based on how "normal" your piercing looks, a gauge that's off by even one size won't fit properly. A quick message to your piercer or a proper sizing tool beats guesswork every time.