Ring Sizing Guide — Everything You Need to Know

Ring sizing is genuinely difficult. Fingers change size throughout the day — they are larger in the evening and after exercise, smaller in cold weather and first thing in the morning. The difference can be half a size or more. This means that even a professional sizing can be slightly off, and adjustments after delivery are common and expected.

At Jabour & Co., we offer one complimentary resize within six months of delivery. Here is what you need to know before you get to that point.

The easiest method: borrow a ring

If your partner wears rings, borrowing one from the correct finger is the most reliable at-home method. The ring finger is typically the fourth finger of the left hand. Take the borrowed ring to any jeweller — or to us — and we will measure the inner diameter precisely.

The string method

Cut a thin strip of paper or string, approximately 10cm long. Wrap it snugly around the finger — not tight, but without gaps. Mark where the paper meets itself. Measure the length in millimetres. Divide by 3.14159 to get the inner diameter, then cross-reference against a UK ring size chart.

As a reference: the average UK women's ring size is approximately L to M. If you are guessing, L is the statistically safest starting point.

Getting sized professionally

We recommend visiting us. Sizing done with proper ring mandrels, at the right time of day (afternoon, not morning), with ring width taken into account (wider bands fit more tightly) gives a result that at-home methods cannot match.

We offer free sizing appointments at our Hatton Garden atelier, or a complimentary ring sizer by post anywhere in the UK. No purchase required.

A note on secret proposals

If you are buying a ring as a surprise, a slightly large ring is always preferable to a tight one. A ring that is too small cannot go on the finger at all. A ring that is slightly large can be worn temporarily and sized down. We have sized hundreds of surprise proposal rings. It is, genuinely, the most enjoyable part of our work.