Find your size

Lumo Ring comes in US sizes 7 to 13. The ring should feel snug but slide over the knuckle without force. Most people wear it on the index finger, the middle finger works too.

If you already own a ring that fits

Measure the inside diameter of that ring in millimetres and match it below.

US size Inside diameter Circumference
7 17.3 mm 54.4 mm
8 18.2 mm 57.0 mm
9 18.9 mm 59.5 mm
10 19.8 mm 62.1 mm
11 20.6 mm 64.6 mm
12 21.4 mm 67.2 mm
13 22.2 mm 69.7 mm

If you do not

Wrap a thin strip of paper around the base of the finger, mark where it overlaps, and measure the length in millimetres. Measure in the evening, when fingers are largest, and go up a size if you land between two.

Wrong size? We swap it

Write to us within 30 days with your order number and the size you need. We ship the new size right away and send a free return label for the first one.