Earring Gauge Sizes Explained: 20G vs 18G vs 16G, Which One Is Right for You?

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.

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: 20G can feel loose or even fall out of piercings that have widened slightly over time from heavy earring wear. If your lobe piercing was done years ago and feels slightly 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 for a while

• 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

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 are shopping for flat back threadless studs - the most comfortable and versatile piercing jewelry format - gauge is especially important because the post and the decorative top are separate pieces. They must match in gauge to connect correctly.

At Shemisli, our threadless flat back studs are available in 20G, 18G, and 16G. If you already own a flat back post and want to add new tops, make sure the top you purchase matches the gauge of your existing post.

The threadless system works by tension - the pin on the back of the top bends slightly and locks into the post. A 16G top will not seat correctly in an 18G post, and vice versa. When in doubt, buy the post and top together so they are guaranteed to match.

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.

Shop Flat Back Studs (20G / 18G / 16G) →

Shop Nose and Septum Jewelry (18G / 16G) →

FAQ

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 gauge flat back studs does Shemisli carry?

Shemisli threadless flat back studs are available in 20G, 18G, and 16G. Nose and septum jewelry is available in 18G and 16G. The gauge is listed on each product page.