Piercing Size & Gauge Guide
Getting the right size isn't a nice-to-have when it comes to piercing jewellery — it's the difference between a piece that sits comfortably and one that either won't fit at all, or moves around and irritates a piercing that's trying to heal or stay settled. This guide covers everything: what gauge actually means, how it varies by piercing location, and where to find exact sizing for your specific piece.
What Is "Gauge," and Why Does It Matter?
Gauge refers to the thickness of the post or bar — not the length, not the style, just how thick the metal is. It's measured in millimetres but referred to by a gauge number, which confusingly runs in reverse: a higher gauge number means a thinner post.
| Gauge | Millimetres | Typically used for |
|---|---|---|
| 20G | 0.8mm | Gun-pierced lobes |
| 18G | 1.0mm | Nose piercings |
| 16G | 1.2mm | Most cartilage piercings (helix, tragus, conch, rook, daith, forward helix) and needle-pierced lobes |
| 14G | 1.6mm | Nipple and belly piercings |
Wearing the wrong gauge doesn't just mean a loose or tight fit at the moment — worn long enough, it can actually change your piercing. Too thin a post can let a healed piercing shrink around it over time; too thick won't fit the channel at all.
Post Length vs. Ring Diameter
Gauge is only half the equation. The other half depends on the jewellery style:
- Flat-back / threadless studs are sized by post length — how far the post extends from the back plate to the front of the piece. This needs to match the thickness of your specific piercing site.
- Segment rings and hoops are sized by inner diameter — how wide the ring is on the inside. This needs to be large enough to comfortably travel around your ear or piercing site without pulling.
Both vary significantly by piercing location, since cartilage thickness and piercing placement differ across the ear and body.
Find Your Exact Size
For detailed, piercing-by-piercing sizing:
- Flat Back Size Guide — post length by piercing location, plus nose, nipple, and gun-pierced lobe gauges
- Segment Ring Size Guide — inner diameter by piercing location
Not sure what you currently have, or shopping to replace existing jewellery? See How to Measure Your Piercing Gauge & Post Length at Home for a step-by-step method using tools you likely already have.
New vs. Healed Piercings
Sizing recommendations in our guides are for fully healed piercings. Fresh piercings need extra room to accommodate swelling — typically a longer post initially, sized down once healing is complete. For piercing-specific healing timelines and downsizing schedules, see our Shop By Piercing guide.
Frequently Asked Questions
What happens if I wear the wrong gauge?
Too thin, worn long-term, and a healed piercing can shrink around it, making it harder to switch back to the correct gauge later. Too thick, and it simply won't fit through the piercing channel.
Can I change gauges once a piercing is healed?
Sizing up slightly is usually fine. Sizing down significantly isn't recommended, since your piercing has healed to match its original gauge — going much thinner risks shrinkage.
Why don't all my piercings use the same gauge?
Different piercing sites use different standard gauges based on tissue type and industry convention — cartilage is generally 16G, nose is finer at 18G, and nipple/belly piercings use a thicker 14G. See the table above for the full breakdown.
Still unsure what size to order? Contact us with your piercing type or current measurements and we're happy to help.