The Cartier Love Ring is one of the most popular rings in the world: its sweet and moving backstory coupled with its sleek, ultra-wearable design make it a veritable fan favorite. However, many of those who want to pick up a piece for themselves can often get confused by Cartier’s ring sizing system, which is quite different from that of other jewelry companies. We’re here to answer your questions and help you find your correctly sized Cartier Love Ring.

Why is Cartier’s sizing system so different from everybody else’s?
Cartier’s sizing system for rings follows that of France, the maison’s home country, as well as Austria, Germany, Belgium, and Scandinavia. This system is the simplest, as it is based on the circumference of your finger in millimeters. In fact, this system follows the recommendations for ring sizing by the International Standardization Organization. Cartier’s sizing system is ideal in its simplicity and ease of use.

Can I use a ring I already own to find my Cartier ring size?
Of course! Cartier’s website actually has a full document, accessible through this link, that you can use to find your Cartier ring size in several different ways. One of the first ways to do so is to print out the document, making sure everything is exactly to scale as they say to do in the instructions, and find the circle that perfectly aligns to the inner circumference of your ring. The circle that fits will indicate what size you are.

I know my U.S. ring size. How can I find out what that translates to in Cartier’s sizing system?
The simplest way to convert your U.S. ring size to Cartier’s ring size is to use the chart that they supply in their sizing guide document, which we linked to above. The chart goes from U.S. size 3 to U.S. size 13 and ¼.

If you feel like doing a little math, you can also use this equation to find your Cartier size using your U.S. size: Cartier Size = (2.55 x U.S. Size) + 36.5. If the answer is a decimal, round up to the next whole number.

If you’re interested in finding your U.S. ring size, we’ve put together this chart to help you measure your fingers correctly or use rings you already have to find your size!