Find your
perfect size.
A ring that fits well never asks for your attention. It simply belongs. Below, four quiet tools to find the size that moves with you — no guesswork, no tape measure required.
Measure without leaving the page.
First calibrate your screen with any bank card — then the tools below read in true millimeters.
Pick a reference object, hold it against the outline, and slide until the widths match exactly. On a phone, choose a coin — a card is wider than the screen.
This on-screen method is a close guide, not a guaranteed exact fit. For certainty, order a ring sizer.
Drag the dial until the circle fits just inside one of your rings.
Enter the inside circumference in millimeters.
No ring to measure? Download our printable sizer, print at 100% (Actual Size), then lay a ring over the circles or wrap the finger strip. Check the printed ruler reads exactly 80 mm.
DOWNLOAD PRINTABLE SIZER (PDF)Every system, one table.
Three ways to measure at home
Take one that already fits and match its inner circle to the gauge above.
A slip of paper around the base of your finger, marked and measured on the ruler.
A few things that quietly change the fit
Wide bands sit tighter. For anything over 6mm, size up a quarter.
If your knuckle is larger than the base, choose a size that slides over it comfortably.
Fingers swell in heat and evening. Measure warm, at day's end, for a true fit.
Ring Size Guide FAQs
What is the most common ring size for women?+
The most common women's ring size in the US is 6 to 6½ — roughly 16.5mm to 16.9mm inner diameter, equivalent to UK L½–M½ and European 51¾–53. Average finger size varies with overall frame, so this is a starting point, not a rule. A woman with smaller hands typically measures US 4–5½, and a woman with larger hands measures US 7½–9. For a surprise engagement ring, never assume an average — measure a ring she already wears.
What is the most common ring size for men?+
The most common men's ring size in the US is 9 to 10½ — roughly 18.9mm to 20.2mm inner diameter, or UK R½–U½ and European 59¼–63. Wide men's wedding bands usually require going up a quarter size from a thin band measurement. If you're sizing for a tungsten or Damascus steel band, that adjustment matters — these metals can't be resized.
How do UK and US ring sizes convert?+
UK ring sizes use letters (A through Z, plus Z+1 and Z+2 for the largest sizes), while US sizes use numbers (3 through 13½). A US 6 is UK L½, a US 7 is UK N½, a US 8 is UK P½, and a US 9 is UK R½. When ordering from a US jeweler in the UK, give your inner diameter in millimeters as a backup — it removes any chance of a letter/number conversion error.
What does European ring size 54 mean in US?+
European ring sizes are simply the inner circumference of the ring in millimetres. A European 54 means the ring measures 54mm around the inside — which corresponds to a US 7 and a UK N½. European 57 is US 8, European 60½ is US 9½, and European 63 is US 10½. Because the European system uses direct measurement in whole millimeters, you may occasionally see half-millimeter sizes (54¼, 55½) when a jeweler is converting from another system.
What if I'm between two sizes?+
Solid gold and platinum rings can typically be resized up to two sizes in either direction. We do not resize sterling silver, gold vermeil or black ruthenium rings, and tungsten, titanium, Damascus steel, and fully stone-set eternity bands cannot be resized at all. For those metals, use the free size exchange if your ring is eligible; sterling silver and gold vermeil can also be resized by a local jeweler. Solid gold and platinum rings include one free resizing within 30 days of delivery.
What if the ring is a surprise gift and the size is wrong?+
For U.S. orders, Aquamarise® offers one complimentary size exchange on eligible designs, provided the ring is not customized or engraved. This allows you to shop with confidence, even when purchasing a surprise gift.
Customized or engraved items are final sale and not eligible for size exchanges. Solid gold and platinum rings include one free resizing within 30 days of delivery. For full details and eligibility requirements, please review our Care & Warranty Policy or contact our team before placing your order.
How do I measure my ring size without a ring sizer?+
Wrap a thin paper strip or non-stretchy string around the base of the finger, mark where the ends meet, and measure the length in millimetres against a ruler. That number is your finger's circumference — a US 6 is 51.9mm; a US 8 is 57.0mm. Take the measurement at the end of the day and repeat it twice for accuracy. Alternatively, lay a ring that already fits on a ruler and measure the inner diameter in millimetres — this is more accurate than string.
Are international ring sizes different?+
Yes. Aquamarise® uses U.S. sizing, but the conversion chart above is available for many countries’ sizes.
Can temperature affect fit during the day?+
Yes. Fingers may swell slightly in the afternoon or after activity. Measuring at the end of the day provides the most accurate result.
How can ring size be measured without the person knowing?+
Trace the inner circle of a ring they already wear or press it into a bar of soap to capture the shape. Compare the imprint to the Aquamarise® size chart.
How does band width affect my size?+
Yes. A wide band (6mm or wider) sits against more skin and feels significantly tighter than a thin band of the same nominal size. For men's wedding bands in the 6–8mm range, size up by a quarter to half size. For the widest styles — 8mm+ — size up by a half size. If possible, try on a sample band in the exact width you plan to order before committing to a size.
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