Find the watch case diameter, lug-to-lug and strap width that fit your wrist. Enter your measurements, pick a style, and get an instant, proportion-based recommendation that works for any brand.
Leave blank and we estimate it from your circumference. Used to cap the lug-to-lug so the watch never overhangs your wrist.
A photo helps you eyeball the fit against the recommended case size. Images stay on your device — nothing is uploaded.
Guidance based on wrist proportion. Personal taste, dial design and case thickness also affect how a watch wears.
Watch fit comes down to proportion, not a single "right" number. Three measurements decide whether a watch sits well on your wrist:
The width of the case, edge to edge (excluding the crown). It should scale with your wrist circumference — bigger wrists carry bigger cases.
The vertical span between the lug tips. This must stay within the flat top of your wrist, or the lugs overhang and the watch looks oversized regardless of diameter.
The lug width where the strap attaches — conventionally about half the case diameter (a 40 mm watch takes a 20 mm strap).
Your style shifts the sweet spot: dress watches look best a notch smaller and slimmer, sports watches sit at the standard size, and oversized cases push a couple of millimetres larger for a bolder look.
A quick reference for case diameter, lug-to-lug and strap width by wrist size (standard/sports proportions).
| Wrist (in) | Wrist (cm) | Case diameter | Max lug-to-lug | Strap width | Fit |
|---|---|---|---|---|---|
| 5.5" | 14 cm | 34–38 mm | ≤ 44 mm | 18 mm | Small |
| 6.0" | 15 cm | 36–40 mm | ≤ 46 mm | 18–20 mm | Small |
| 6.5" | 16.5 cm | 38–41 mm | ≤ 48 mm | 20 mm | Medium |
| 7.0" | 18 cm | 39–42 mm | ≤ 50 mm | 20–22 mm | Medium |
| 7.5" | 19 cm | 41–44 mm | ≤ 52 mm | 22 mm | Large |
| 8.0" | 20.5 cm | 43–46 mm | ≤ 54 mm | 22–24 mm | Large |
| 8.5" | 21.5 cm | 44–48 mm | ≤ 56 mm | 24 mm | Extra-large |
Measure your wrist circumference with a flexible tape or a strip of paper, choose your preferred style, and the calculator matches you to a case-diameter range, a maximum lug-to-lug length and a strap width. As a rule of thumb, a 6–7 inch (15–18 cm) wrist suits a 38–42 mm case, while wrists above 7.5 inches (19 cm) can carry 42–46 mm comfortably.
Lug-to-lug is the distance from the tip of the top lugs to the tip of the bottom lugs — the true vertical footprint of a watch. It matters more than case diameter for fit: if the lug-to-lug is longer than the flat top of your wrist, the lugs overhang and the watch looks awkward. Keep lug-to-lug at or below your wrist width.
Lug width is usually about half the case diameter. A 40 mm watch typically takes a 20 mm strap, a 42 mm watch a 22 mm strap. The calculator returns the conventional even-numbered width for your recommended case size.
No. Trends have moved back toward 36–40 mm cases. Proportion to your wrist matters far more than raw size — a well-proportioned 39 mm watch looks more considered than an oversized case that overhangs the wrist.
Yes. The recommendation is driven by wrist measurement and style preference, not gender. Smaller wrists (under 15 cm) are guided toward 32–38 mm cases, which covers most unisex and women's models.
Best case sizes for a smaller 6" (15 cm) wrist.
The medium 6.5" (16.5 cm) wrist sweet spot.
The versatile 7" (18 cm) wrist explained.
Sizing a larger 7.5" (19 cm) wrist.
Big-watch options for an 8" (20 cm) wrist.
How 2 mm changes the look and fit.
Three accurate ways to measure for a watch.