Seamaster Diver 300M Black Chronograph Men's Watch | OM 210.32.44.51.01.001

Three ways to get the fit right the first time. If you're ever between sizes, size up — and if a size doesn't work out, our easy 30-day return policy has you covered.

Ring sizes (US)

The most reliable method: take a ring that already fits the intended finger and measure its inner diameter in millimeters with a ruler, then match it below. Fingers swell slightly in heat and in the evening — measure at the end of the day for the truest fit.

No ring to measure? Wrap a thin strip of paper snugly around the base of the finger, mark where it overlaps, measure the length in millimeters, and match it to the circumference column. Wide bands wear snugger than thin ones — for wide styles, consider going up a half size if available.

Necklace lengths

Lengths are measured end to end, clasp included. For layering, keep at least 2" between chains.

Bracelet sizing

Measure your wrist just below the wrist bone with a soft tape (or a strip of paper measured against a ruler), keeping it snug but not tight. Then add ease depending on the fit you want:

Typical reference: women's wrists average 6"–6.5" (bracelet 6.5"–7.5"), men's 7"–7.5" (bracelet 7.5"–8.5").

Still unsure? Contact us with your measurements and the piece you're considering — we'll recommend a size.