Earring Size Tool: See Studs & Gauges at Actual Size
Calibrate your screen with a bank card, then preview any stud size from 2mm to 14mm at true scale, and convert ear gauges to millimeters and inches.
The copper coin is a US penny (19.05 mm) for scale.
Make it truly actual size
Screens differ. Hold a credit card (or any ID-1 card) against the screen and drag until the dashed outline matches it exactly. We remember the setting on this device.
How to use it
- Hold any standard bank, ID or gift card flat against your screen.
- Drag the calibration slider until the dashed outline matches the card edges exactly.
- Now slide through stud sizes. What you see is the real diameter of the earring face.
Without calibration we use the standard CSS scale (96 px per inch), which is close on most laptops but can be off on phones and high-density displays.
Stud sizes at a glance
| Size | Inches | Looks like |
|---|---|---|
| 2 mm | 0.079 in | A pinhead; ultra-minimal second-hole stud |
| 3 mm | 0.118 in | Tiny sparkle, great for cartilage |
| 4 mm | 0.157 in | Classic small stud, kid-friendly |
| 5 mm | 0.197 in | Everyday stud, slightly smaller than a pencil eraser |
| 6 mm | 0.236 in | About a pencil eraser; noticeable |
| 7 mm | 0.276 in | A pea; reads as a statement for small lobes |
| 8 mm | 0.315 in | A chickpea; bold everyday stud |
| 10 mm | 0.394 in | Statement stud or small button earring |
| 12 mm | 0.472 in | Button earring; covers most of a small lobe |
More detail in our 5mm earrings actual size and 8mm earrings actual size guides.
Ear gauge converter
Gauge numbers run backwards: the bigger the number, the thinner the post. Most lobe earrings are 20g or 18g; cartilage jewelry is usually 16g. Pick a size to see it in millimeters and inches.
Full chart and stretching advice: ear gauge size chart · what gauge are regular earrings?