Yes, you can figure out piercing gauge by measuring the jewelry’s thickness with calipers or by matching it to a verified gauge chart.
You’re here to size jewelry without drama. This guide shows clear steps, tools that work, and the exact checks a pro would make. By the end, you’ll know which gauge you have, what that number means in millimeters, and how to swap jewelry without irritation.
How To Figure Out Your Piercing Gauge: Step-By-Step
Start by deciding whether you’ll measure the jewelry you’re wearing or a spare piece you can remove. Either way, clean hands and a calm setup help. If the piercing is fresh or cranky, ask a studio to help rather than wrestling with it at home.
What You’ll Need
- Digital or analog calipers that read in millimeters.
- A printed or metal gauge card, if you have one.
- Good light and a lint-free wipe to dry the jewelry.
Quick Method
- Remove the jewelry if it’s fully healed and easy to take out. If not, use a spare with the same style and thickness.
- Zero the calipers, then close the jaws gently on the thickest part of the post or ring. Read the millimeter value.
- Convert that millimeter reading to a gauge number using the table below or a trusted chart.
- Write the size down so you can reorder or match ends later.
Common Piercing Gauges And Millimeters
Gauge is the thickness of the post or ring wire. The number runs backward: smaller numbers mean thicker jewelry. Use this broad table as a starting point; studios can pierce at other sizes to suit anatomy and jewelry style.
| Piercing | Typical Gauge | Notes |
|---|---|---|
| Lobe | 20g–18g | Many shops start at 18g; older gun piercings may be 20g. |
| Nostril | 18g–20g | Studs often 18g; some regions favor 20g for thin posts. |
| Septum | 16g | Occasionally 14g for thicker jewelry or stretching paths. |
| Helix/Cartilage | 16g–18g | Labrets and barbells in 16g are common for cartilage. |
| Tragus/Daith | 16g | Curved or ring styles vary; check inner diameter too. |
| Tongue | 14g | Often downsized after swelling; keep the same gauge. |
| Navel | 14g | Banana barbells use 14g; length matters for fit. |
| Nipple | 14g–12g | Some choose 12g for a sturdier feel. |
| Eyebrow | 16g | Usually a short curved barbell. |
| Genital (varies) | 12g–10g+ | Often thicker for comfort and stability. |
Wearers who stretch earlobes or septums move to lower gauge numbers over time. Slow pacing and quality jewelry keep tissue happy and reduce setbacks.
What The Numbers Mean
Here’s the plain-English bit. Gauge matches to millimeters. An 18g post is thinner than a 16g post; 14g is thicker still. When you reach 0g and 00g, you’re in plug and tunnel territory. Jewelers also list inch fractions for tunnels and plugs, so a quick conversion chart saves headaches.
Gauge To Millimeter Basics
- 20g ≈ 0.8 mm
- 18g ≈ 1.0 mm
- 16g ≈ 1.2–1.3 mm
- 14g ≈ 1.6 mm
- 12g ≈ 2.0 mm
- 10g ≈ 2.5 mm
- 8g ≈ 3.2 mm
- 6g ≈ 4.1 mm
- 4g ≈ 5.1 mm
- 2g ≈ 6.5 mm
- 0g ≈ 8.2 mm
- 00g ≈ 9.2–10 mm
Figuring Out Your Piercing Gauge Safely — Pro Tips
If you’re stuck between two readings, round to the nearest standard gauge rather than chasing a weird in-between size. Many jewelry makers follow the same increments, so matching a standard size gives you far more options.
When To Ask A Studio
Get in-person help if the jewelry feels tight, if the piercing is tender, or if you’ve had a recent swap. A piercer can measure with calipers, check fit, and swap ends or bars without stressing the tissue.
Material And Safety Notes
For fresh piercings or sensitive skin, look for implant-grade titanium that matches industry specs. The Association of Professional Piercers lists acceptable materials and markings; see their page on jewelry for initial piercings for clear guidance. Sticking to known materials helps sizing too, since quality makers stick to true gauges rather than off sizes.
Stretching Paths
If you plan to stretch, aim for small jumps and plenty of healing time. The APP’s guide to stretching explains pacing and care. Staying patient keeps the fistula strong and lowers the chance of thin spots or blowouts.
Reading A Gauge Chart The Right Way
Charts list the gauge number with a matching metric value. Read straight across to find the millimeter size, then match that to the post marked on a product page. Some charts add inch fractions for larger plugs and tunnels; those fractions map to the same millimeter values, so you can shop in any format.
Close Calls And Tolerances
You may see small differences across brands. A 16g post can read 1.2 mm on one chart and 1.3 mm on another. That gap is tiny in practice. If the jewelry feels smooth in the channel and the ends seat correctly, you’re fine to wear it.
How Gauge Interacts With Fit
Gauge is only one dimension. Length and inner diameter change comfort, swelling room, and the line of the jewelry. A ring that fits the hole but hugs too close can rub; a bar that’s too short can pinch. Measure all three when you’re changing styles.
Posts And Barbells
Measure the wearable length between the discs or ends. Fresh piercings start longer to allow swelling, then get downsized at the same gauge once things calm down. Keep a note of both lengths: the long starter, and the settled length you wear day to day.
Rings And Clickers
Inner diameter sets how the ring sits. For a snug nostril hoop, many wearers pick an inner diameter near 8–10 mm at 18g or 16g, though anatomy rules the day. For cartilage, a touch more space can help with swelling after a long day or a side sleep.
Tool Choices And Accuracy
Calipers give the best read. A wheel gauge or card can work in a pinch for posts and captive rings, but curved pieces can fool flat templates. A plain ruler can’t grab millimeter fractions with enough precision for small gauges.
| Tool | Accuracy | Best Use |
|---|---|---|
| Digital Calipers | High (0.01 mm) | Any straight post or removable ring. |
| Analog Calipers | High (0.02–0.05 mm) | General sizing at home or in studio. |
| Gauge Card/Wheel | Medium | Quick checks on captive rings and posts. |
| Ruler | Low | Inner diameter and bar length, not gauge. |
| Studio Check | High | When the piercing is new or touchy. |
Mistakes That Throw Off Readings
Measuring The Wrong Spot
Always measure the thickest part that sits in the piercing. Don’t measure a threaded end or a decorative section. A ring with a hinge or clicker has a thinner segment near the clasp, which can trick a card or a ruler.
Reading Curves Like Straights
Curved barbells and segments can rock in flat gauges. If the readout looks off, take a second pass with calipers. Roll the piece between the jaws and watch for jumps. The largest steady reading is your gauge.
Chasing Nonstandard Sizes
Some novelty pieces run off spec. Stick with reputable makers and your sizes will line up with charts and studio gear. If a post won’t take an end that should match, you’re likely dealing with mismatched threading or a cut that’s out of range.
If You Don’t Have Tools
Borrow a spare bar from a friend who knows their size and compare by touch across the shaft, not the end. This can get you close, but it’s a rough guess. A studio check is quick and cheap, and saves a return label.
Signs Your Jewelry Size Is Off
- Ends won’t seat flush or keep loosening.
- The channel feels sore after short wear.
- Discoloration or snagging near the entry or exit.
- A ring lifts away from the line you expect or rubs in one spot.
When Switching Materials
Heavier metals can pull on soft tissue at larger gauges. Titanium and steel hold shape well; gold is softer in thin posts. Keep gauge the same when swapping, and match threading type so ends seat cleanly. For new piercings, stick to implant-grade picks that match industry specs listed by the APP; the guidance on jewelry for initial piercings lays it out clearly.
Storage And Labeling
Small bags with a label for gauge, length, and inner diameter keep your stash tidy. If you own ends in a few styles, write the threading type on the label as well. Future you will thank you when a backing goes missing at 2 a.m.
Mini Glossary
- Gauge: Thickness of the post or ring wire.
- Wearable length: The straight section that sits in the channel.
- Inner diameter: The inside width of a ring or clicker.
- Downsizing: Shortening the bar once swelling settles.
- Threadless: A pin-based end that pressure-fits into a post.
Method Recap Card
- Measure with calipers on a healed piece or a spare.
- Convert millimeters to gauge with a chart.
- Record gauge, length, and inner diameter.
- Match threading type when swapping ends.
- Stick with known materials to keep sizes consistent.
FAQ-Style Checks Without The Fluff
Can You Measure Without Removing Jewelry?
You can measure length and inner diameter while wearing a piece. Gauge is tough to get right in place, which is why calipers on a spare or studio check wins.
Do All Shops Use The Same Gauges?
Shops follow standard steps, yet anatomy and style lead the choice. Bring your numbers so a piercer can confirm and fit the look you want.
How To Shop Once You Know Your Size
Save the gauge, length, and inner diameter in a notes app. When shopping, use filters for those numbers. If you’re mixing ends and posts, match both threading type and gauge so the parts seat flush. Many product pages list millimeters and gauge side by side; use both fields to avoid mix-ups.
Your Next Step
If you came here asking how to figure out your piercing gauge, you now have the tools. Keep a tiny sizing kit at home: calipers, a copy of the gauge chart, and a note with your go-to sizes. If a friend asks you how to figure out your piercing gauge, you can walk them through the same steps in minutes.