The most common question we get is also the simplest: 36 mm or 39 mm? Case size changes how a watch looks and feels more than almost anything else, so it is worth getting right. Here is how to choose.
First, measure your wrist
Wrap a soft tape measure (or a strip of paper) around your wrist just above the wrist bone and note the circumference. As a rough guide: under about 16 cm is a smaller wrist, 16-18 cm is medium, and above 18 cm is larger. This is a starting point, not a hard rule — fit is personal.
The 36 mm: balanced and versatile
A 36 mm case is a classic, genuinely unisex size. It sits neatly on smaller and medium wrists, slips easily under a shirt cuff, and reads as elegant and understated. If you want a watch that dresses up effortlessly, or you prefer a more discreet presence, 36 mm is the timeless choice.
The 39 mm: a fuller presence
At 39 mm the watch makes more of a statement. It suits medium to larger wrists, gives the dial more room to breathe, and leans slightly more sporty and modern while staying very wearable. If you like your watch to be noticed — or you have a larger wrist — 39 mm is the way to go.
Still not sure?
Think about how you will wear it: dressier and more discreet, lean 36 mm; everyday and a touch sportier, lean 39 mm. Both sizes share the same Seiko NH35 automatic movement, sapphire crystal and stainless-steel build, so you are only choosing proportions — never quality.
Most of our collections are offered in both sizes, from the dressy Tolaris to the icon-styled Valtor. Find the one that fits you.