Shemisli Gauge Size Guide: Find Your Perfect Fit

Buying replacement jewelry for a piercing and not sure which gauge you need? You are not alone. Gauge sizing is one of the most confusing parts of the piercing jewelry world - the numbers go in the opposite direction to what you might expect, and getting it wrong means jewelry that either falls out or does not fit at all.

This guide explains exactly what gauge means, how to figure out which size your piercing is, and which gauges Shemisli carries for threadless flat back studs and nose and septum jewelry.

Quick Reference: All Three Gauges at a Glance

Gauge

Diameter

Common use

Shemisli threadless

Shemisli septum

Best for

20G

0.8mm

Standard lobe

✓ Available

-

Standard lobe piercings

18G

1.0mm

Lobe, helix, nose

✓ Available

✓ Available

Helix, nostril, lobe

16G

1.2mm

Cartilage, septum

✓ Available

✓ Available

Cartilage, septum, stretched lobes

What Is Gauge - and Why Do the Numbers Go Backwards?

Gauge is the unit of measurement used for piercing jewelry thickness - specifically the diameter of the post or wire that goes through your piercing.

Here is the part that confuses almost everyone: the higher the gauge number, the thinner the jewelry. 20G is thinner than 18G, which is thinner than 16G. This is because gauge sizing comes from an old wire measurement system where the number represented how many times the wire was drawn through a die - more draws means thinner wire, higher number.

In practical terms: 20G is the thinnest option in everyday piercing jewelry, 16G is the thickest of the three. The difference between them is small - less than half a millimeter across all three sizes - but it matters for fit, comfort, and how your piercing responds.

The Three Gauges - What Each One Is Used For

20 Gauge (20G) - 0.8mm diameter

20G is the thinnest standard piercing jewelry gauge. It is the size most commonly used for standard lobe piercings done with a piercing gun at mall jewelry stores and many general piercing studios. It is also the size of most fashion earrings sold on the high street.

  • Common placements: standard lobe piercings

  • Feel: the lightest and most delicate option - ideal if your lobe piercing is standard-sized and you want something that feels almost invisible

  • Watch out for: In piercings that have widened slightly over time from heavy earring wear, 20G jewelry won't actually fall out, the top and backing hold it securely in place, but it may feel like it's moving around more, or sit slightly lower/looser than it used to. If your lobe piercing was done years ago and feels loose with standard earrings, 18G may be a better fit.

  • Shemisli threadless studs: available in 20G

18 Gauge (18G) - 1.0mm diameter

18G is the middle ground and the most versatile gauge in the Shemisli range. It works for multiple placements - lobe, helix, and nostril - which makes it the most practical choice if you are building a collection of interchangeable pieces.

  • Common placements: lobe piercings, helix and cartilage piercings done by professional piercers, nostril piercings

  • Feel: slightly more substantial than 20G, sits more securely, especially in piercings that have been worn and enlarged over time. Some people continue to wear progressively thicker earrings, and their piercing may have naturally enlarged as a result.

  • Best choice if: you are unsure of your gauge, you want one size that works across ear and nose piercings, or your piercer recommended 18G for your cartilage or nostril

  • Shemisli threadless studs: available in 18G

  • Shemisli nose and septum: available in 18G

16 Gauge (16G) - 1.2mm diameter

16G is the standard gauge for most cartilage piercings done by professional piercers - helix, tragus, conch, daith, rook, and forward helix. It is also the standard for septum piercings. The slightly larger diameter creates a more secure fit in cartilage tissue and reduces the risk of the jewelry migrating or the piercing closing around a too-thin post.

  • Common placements: helix and all cartilage piercings, septum piercings, and lobe piercings that have widened over time from heavy earring use

  • Feel: more presence than 18G or 20G - noticeably more secure in cartilage placements. In a lobe, it feels slightly more substantial but still completely comfortable.

  • Best choice if: your cartilage piercing was done by a professional piercer (most will pierce at 16G), your lobe piercing has widened over years of wearing heavy earrings, or you wear your earrings 24/7 and want maximum security.

  • Shemisli threadless studs: available in 16G

  • Shemisli nose and septum: available in 16G

Quick Reference: All Three Gauges at a Glance

Gauge

Diameter

Common use

Shemisli threadless

Shemisli septum

Best for

20G

0.8mm

Standard lobe

✓ Available

-

Standard lobe piercings

18G

1.0mm

Lobe, helix, nose

✓ Available

✓ Available

Helix, nostril, lobe

16G

1.2mm

Cartilage, septum

✓ Available

✓ Available

Cartilage, septum, stretched lobes


How to Figure Out What Gauge Your Piercing Is

If you are not sure what gauge your existing piercing is, here are the most reliable ways to find out:

  • Ask your piercer: the most accurate option. If you remember where you had it done, contact them - they often keep records or can advise based on the placement.

  • Check your current jewelry: the gauge is sometimes stamped on the back of earrings or packaging. Look for a number followed by G or the abbreviation GA.

  • Default assumptions by placement: standard lobe (piercing gun) = likely 20G. Professional lobe or helix = likely 18G or 16G. Septum = likely 16G or 18G. Cartilage by professional piercer = likely 16G.

  • Try and assess fit: if a piece of jewelry slides through very easily with noticeable looseness, you may need to go up a gauge (lower number). If it feels tight or requires force, go down a gauge (higher number).

Gauge and the Threadless Flat Back System

If you're shopping for flat back threadless studs, gauge works a little differently than you might expect and in a good way.

At Shemisli, our decorative tops are universal across gauges, meaning the same top fits onto backing posts of different thicknesses, 20G, 18G, or 16G. This is what makes the threadless system so versatile: you don't need to buy a separate top for every gauge you own.

For example, if you have one Shemisli top along with both a 20G backing and an 18G backing, you can wear that same top in your lobe (20G) one day, and in your nose (18G) another day, simply by switching which backing post it's attached to. One top, multiple placements, no need to duplicate your favorite designs across every gauge.

This is one of the most practical advantages of the threadless flat back format: you build a collection of tops you love, and mix and match them across whichever gauge backings match your piercings.

Shemisli's threadless flat back studs are available with backing posts in 20G, 18G, and 16G, so you can outfit lobe, cartilage, and nose/septum piercings using the same top designs.

Gauge for Nose and Septum Jewelry

Nose piercing gauge follows the same logic as ear piercing gauge but with slightly different standard sizing depending on the placement:

  • Nostril piercing: most professional nostril piercings are done at 18G. This is the standard size for L-bend, bone, and screw-style nostril studs. Some piercers use 20G for finer placements.

  • Septum piercing: 16G is the standard gauge for septum piercings. The slightly thicker post sits more securely in the septum tissue and is required for most horseshoe and clicker-style septum rings.

Shemisli nose and septum jewelry is available in 18G and 16G. Check the product page for the specific gauge of each piece before purchasing, and match it to what your piercer used.

📐 Hoop Size Guide (Inner Diameter)

Gauge tells you the thickness of a hoop's wire - but for hoops, the millimeter size you'll see on the product page refers to something different: the inner diameter, meaning the open distance across the inside of the ring. This is what determines how snug or loose the hoop sits.

Diameter (mm)

Fit Style & Best Placements

5 mm

Extra snug fit - tiny forward helix, anti-tragus, or very thin cartilage folds

6 mm

Snug fit - rook, daith, tight nose rings, or small helix piercings

7 mm

Standard fit - the most popular size for everyday helix, tragus, and comfortable nose hoops

8 mm

Snug fit for the earlobe, this is usually the minimum size for lobe piercings 

10 mm

Loose/dangle fit - lower earlobes, conch piercings, or a looser hoop look


💡 Pro tip: For a tight, seamless hoop look, choose 5mm or 6mm. For a comfortable, moving fit, choose 7mm or 10mm.

📏 Flat Back Stud Size Guide (Post Length)

For flat back (threadless/labret) studs, the millimeter size refers to the wearable length of the post, measured from the flat back disc to where the decorative top sits, not including the top design itself.

Length

Best For

5 mm (Short)

Thin cartilage folds or fully healed piercings where you want a flush, zero-gap fit

6 mm (Standard)

The universal standard length for helix, tragus, and earlobe piercings - fits most ears perfectly

7 mm (Comfort)

Thicker earlobes or cartilage - gives a little breathing room for easy cleaning

8 mm

For thicker earlobes needing extra length beyond the standard comfort fit

10 mm (Long)

Fresh piercings to accommodate initial swelling, or very thick conch areas

⚠️ Quick Measuring Tips

  • Measure existing jewelry: the easiest way to find your size is to measure a piece that already fits you well using a millimeter ruler.

  • When in doubt, size up: jewelry that's too tight can cause pressure, irritation, or pain. If you're between two sizes, choose the larger one.


What gauge is a standard lobe piercing?

Most standard lobe piercings done with a piercing gun are 20G (0.8mm). Lobe piercings done by professional piercers are often 18G (1.0mm) or 16G (1.2mm), which create a slightly more secure fit and heal better with quality jewelry.

What gauge are helix and cartilage piercings?

Most cartilage piercings done by professional piercers are 16G (1.2mm). Some piercers use 18G for finer placements or smaller ear anatomy. If you are unsure, check with your piercer - buying the wrong gauge means the jewelry will not fit.

What gauge is a septum piercing?

Most septum piercings are 16G (1.2mm). This is the standard gauge for horseshoe barbells and septum clicker rings. Shemisli septum jewelry is available in 16G and 18G - check the product listing for the specific piece you are purchasing.

Can I put a 16G earring in an 18G piercing?

No - 16G is thicker than 18G, and forcing a thicker post through a smaller piercing can cause tearing and irritation. You should match the gauge of your jewelry to your piercing exactly. If you want to size up, this should be done gradually with the guidance of a professional piercer.

Can I put an 18G or 20G earring in a 16G piercing?

Technically yes, but thinner jewelry in a larger piercing may feel loose and can cause the piercing to shrink over time around the thinner post. For the best fit and comfort, always match gauge to your piercing size.

What hoop diameter should I choose for a snug look?

5mm or 6mm gives the tightest, most seamless hoop look, best suited to smaller placements like forward helix or daith.

How do I know what length flat back stud I need? 6mm fits most standard helix, tragus, and earlobe piercings. If your piercing is fresh and still swollen, or your cartilage is on the thicker side, size up to 7mm or 10mm.

What gauge flat back studs does Shemisli carry?

Threadless flat back studs are available in 20G, 18G, and 16G, with post lengths of 5mm, 6mm, 7mm, 8mm and 10mm. Hoops are available in 5mm, 6mm, 7mm, and 10mm inner diameter. Nose and septum jewelry is available in 18G and 16G. Exact sizing is listed on each product page.