⚡ Quick Answer (30 seconds)
- Gauge = post thickness. Higher number = thinner jewelry. 20G (0.8mm) is thinnest; 00G (9.3mm) is very large.
- Common gauges: Nostril 20G; Ear lobe 18G; Belly/nipple 14G; Ear stretched 8G-00G.
- 1G jump ≈ 0.25-0.5mm difference. Chart and per-piercing guide below.
→ Full gauge chart, conversion table, and piercing-specific sizes below.
Piercing gauges confuse almost everyone the first time. Not just the “higher number = thinner” reverse logic — but that different piercings use wildly different standards, ears use different gauges above a certain size, and stretching doubles the confusion. This guide is the one chart you need: every gauge in mm and inches, standards by piercing type, and what to know before buying jewelry.
Complete Piercing Gauge Chart
| Gauge | mm | Inch | Uses |
|---|---|---|---|
| 20G | 0.8 mm | 0.032″ | Nostril, rook, daith, tragus (fine) |
| 18G | 1.0 mm | 0.040″ | Ear lobe, helix, cartilage, nostril |
| 16G | 1.2 mm | 0.047″ | Cartilage (standard), eyebrow, lip, conch |
| 14G | 1.6 mm | 0.063″ | Belly button, nipple, tongue, Prince Albert |
| 12G | 2.0 mm | 0.078″ | Stretched piercings, heavier nipple/belly |
| 10G | 2.4 mm | 0.094″ | Starting ear stretching, PA stretched |
| 8G | 3.2 mm | 0.125″ | Ear stretching intermediate |
| 6G | 4.0 mm | 0.156″ | Ear stretching advanced |
| 4G | 5.0 mm | 0.200″ | Ear gauges |
| 2G | 6.0 mm | 0.235″ | Larger ear gauges |
| 0G | 8.0 mm | 0.315″ | Large ear stretching |
| 00G | 9.3 mm | 0.375″ | Very large ear stretching |
| 1/2″ | 12.7 mm | 0.500″ | Beyond 00G (inch measurements) |
| 5/8″ | 15.9 mm | 0.625″ | Large lobe stretching |
Standard Gauges by Piercing
Ear Piercings
- Standard lobe: 20G-18G
- Helix: 18G-16G
- Tragus/rook/daith: 16G
- Conch: 16G-14G
- Industrial barbell: 14G-16G
Facial
- Nostril: 20G-18G
- Septum: 16G-14G
- Bridge: 16G-14G
- Eyebrow: 16G-14G
- Labret/lip: 16G-14G
- Monroe/Medusa: 16G
Oral
- Tongue: 14G (standard), 12G (heavy)
- Tongue web/smiley: 16G
- Venom: 14G-16G
Torso
- Belly button: 14G
- Nipple: 14G (standard), 12G (common for stretched)
- Microdermal: 14G anchor
- Surface: 14G barbell or anchor
Genital
- Prince Albert: 14G-10G (typically 12G)
- Frenum: 14G
- Dydoe: 14G-12G
- Labia/clitoral hood: 14G-16G
- Triangle: 14G
Why the Number System Is Reversed
Piercing gauges come from the American Wire Gauge (AWG) system, historically used for wire and metal rod thickness. The number represents how many times the wire was drawn through smaller dies — more draws = thinner wire. So a 20G wire was drawn 20 times; a 00G wire was drawn zero times (still in its original thick form).
Once you pass 0G, the system switches to fractions of an inch (1/2″, 5/8″, 3/4″), because AWG below 00 gets mathematically awkward.
✨ Shop by Gauge
TBR organizes all body jewelry by gauge for easy shopping. Filter to your exact size in titanium, gold, or niobium.
Stretching Sizes
Ear stretching typically moves one gauge at a time, with minimum 6-8 weeks between steps. Going too fast causes tearing, blowouts, and permanent lobe damage. Common stretching path:
- 18G → 16G → 14G → 12G → 10G → 8G → 6G → 4G → 2G → 0G → 00G
- After 00G: 7/16″ → 1/2″ → 9/16″ → 5/8″ → 3/4″
If you reach a size that doesn’t feel right or bleeds, downsize back one step and wait 2-3 months before trying again. There’s no rush.
How to Measure Your Current Jewelry
- Use a caliper or precision ruler
- Measure the diameter of the post (the bar that goes through your piercing) — not the gems or balls
- Convert mm to gauge using the chart above
- If between sizes, err on the thicker side for your body — thinner jewelry can tear slightly stretched piercings
For professional sizing help, refer to the Association of Professional Piercers (APP).
Frequently Asked Questions
What gauge is a standard ear piercing?
20G or 18G for ear lobes. Most piercing guns use 18G studs. Professional piercers often use 16G for better long-term healing and jewelry options.
What gauge is a belly button piercing?
14G (1.6mm). This is the standard for belly piercings. Most commercial belly jewelry is designed for 14G posts; smaller gauges will leave a loose piercing that can migrate.
Is 16G smaller or bigger than 14G?
16G is thinner than 14G. The numbers work in reverse — higher number = thinner post. 16G = 1.2mm; 14G = 1.6mm.
Can I downsize my piercing gauge?
Yes, but your piercing may shrink over time (months to years) to fit the new gauge. For stretched piercings, tissue usually won’t fully return to original size — expect a looser piercing.
What gauge is a tongue piercing?
14G is the universal standard. Going thinner (16G) has higher tear risk during tongue movement; going thicker (12G) is usually only for stretched tongue piercings.
How fast can I stretch my ear piercings?
Minimum 6-8 weeks per gauge step. Longer intervals (10-12 weeks) produce better long-term results. Faster stretching causes blowouts, tearing, and uneven scars.
What gauge do piercing guns use?
Usually 18G, sometimes 20G. This is too thin for good healing on cartilage. Professional needle piercings at 16G heal better and last longer.
Can I mix gauges in the same ear?
Yes — different piercings can have different gauges. Stacked lobes might use 18G, 16G, and 14G depending on placement. Each piercing has its own optimum gauge.
About the author
Mona Lin — Head of Piercing Education at The Body Rings. APP member, 10+ years professional body piercing experience.