Sizing

Every ARCA ring is crafted to order in the size you choose. A moment spent confirming that size ensures your ring fits beautifully from the first day you wear it.

A few considerations

Fingers change subtly through the day and with the seasons. For the truest measurement, size the exact finger you plan to wear the ring on, late in the day and at a comfortable room temperature, when your hands are at their fullest.

Three ways to find your size

1. With a jeweler

A jeweler can measure your finger on a ring mandrel in a matter of minutes, usually as a complimentary service. This is the most precise method and the one we recommend. Ask for your US size as a number, including any quarter size.

2. From a ring you already own

Choose a ring that fits the intended finger comfortably, lay it flat, and measure the inside diameter from edge to edge. Then match that measurement to the nearest size in the chart below. All sizes shown are US ring sizes.

US size	Inside diameter	Inside circumference
2.5	13.7 mm 0.54 in	42.9 mm 1.69 in
3	14.1 mm 0.55 in	44.2 mm 1.74 in
3.5	14.5 mm 0.57 in	45.5 mm 1.79 in
4	14.9 mm 0.59 in	46.8 mm 1.84 in
4.5	15.3 mm 0.60 in	48.0 mm 1.89 in
5	15.7 mm 0.62 in	49.3 mm 1.94 in
5.5	16.1 mm 0.63 in	50.6 mm 1.99 in
6	16.5 mm 0.65 in	51.9 mm 2.04 in
6.5	16.9 mm 0.67 in	53.1 mm 2.09 in
7	17.3 mm 0.68 in	54.4 mm 2.14 in
7.5	17.7 mm 0.70 in	55.7 mm 2.19 in
8	18.1 mm 0.71 in	57.0 mm 2.24 in
8.5	18.5 mm 0.73 in	58.3 mm 2.29 in
9	19.0 mm 0.75 in	59.5 mm 2.34 in
9.5	19.4 mm 0.76 in	60.8 mm 2.39 in
10	19.8 mm 0.78 in	62.1 mm 2.44 in
10.5	20.2 mm 0.79 in	63.4 mm 2.49 in
11	20.6 mm 0.81 in	64.6 mm 2.54 in
11.5	21.0 mm 0.83 in	65.9 mm 2.59 in
12	21.4 mm 0.84 in	67.2 mm 2.65 in
12.5	21.8 mm 0.86 in	68.5 mm 2.70 in
13	22.2 mm 0.87 in	69.7 mm 2.75 in

3. With us

We will guide you through measuring your finger with care. This is complimentary.

Request an appointment

Sizes we craft

The sizes available for each piece are listed on its product page. Quarter sizes are available on request at no additional cost. Select the nearest size and add a note in your cart with the quarter size you would like, and we will craft your ring to it.

If your size falls outside the range shown for a piece, contact us and we will guide you through what is possible.