Ring Size Conversion Chart shows ring sizes in both mm and inches, plus internal diameter.
Ring size conversion for international ring sizes can vary slightly depending on the country and the specific sizing system used. The two most commonly used international ring size systems are:
US Ring Size: This is the most common system in the United States and Canada, and it uses a numerical scale. Ring sizes typically range from US size 3 to 13.5, with half sizes available.
UK Ring Size: The United Kingdom and Australia use a letter-based system. The sizes range from A (the smallest) to Z+3 (the largest).