How to Use This Calculator

Select Input Type
Choose how you know the ring size
(US size, UK size, EU size, Indian size, Diameter, or Circumference).

Select the Value
Choose the correct size or measurement from the dropdown.

Select Band Width
Choose the band width of the ring.
Wider rings need extra comfort space.

Click Calculate
The calculator will show:

• All international ring sizes

• Inner diameter in mm

• Final CAD size with comfort-fit

For CAD & Jewelry Making

• Use Final CAD Diameter for modeling and production

• Comfort-fit helps the ring feel better and reduces resizing

Measurement Tip

• Measure an existing ring for best accuracy

• Use mm for better precision