Watch Size Calculator
Enter your wrist circumference below to get a recommended case diameter, lug-to-lug, and thickness range — based on proven proportion rules used by watchmakers and collectors.
Size Recommender
Enter your wrist circumference. Choose millimetres or inches.
Measured around the wrist bone where the watch sits. Recommendations are guidelines — personal style, case shape, and strap choice also affect how a watch wears.
How to measure your wrist
- 1. Grab a flexible tape, string, or strip of paper. Anything you can wrap around your wrist.
- 2. Wrap it once, just above the wrist bone. This is where a watch usually sits. Keep it snug but not tight.
- 3. Mark the overlap. If using string or paper, mark where it meets and measure with a ruler.
- 4. Use millimetres for best precision. Inches work too — the calculator accepts both.
Tip: measure at the end of the day, when your wrist is slightly fuller. A watch that fits when you're warm won't feel tight in the evening.
Wrist-to-case size chart
| Wrist (circumference) | Case diameter | Lug-to-lug | Best styles |
|---|---|---|---|
| 140 - 155 mm (5.5 - 6.1 in) | 34 - 38 mm | 38 - 44 mm | Dress, small sport |
| 155 - 170 mm (6.1 - 6.7 in) | 36 - 40 mm | 42 - 48 mm | Most everyday watches |
| 170 - 185 mm (6.7 - 7.3 in) | 38 - 42 mm | 44 - 50 mm | Sport, diver, chrono |
| 185 - 200 mm (7.3 - 7.9 in) | 40 - 44 mm | 46 - 52 mm | Larger sport, pilot |
| 200 mm+ (7.9 in+) | 42 - 46 mm | 48 - 56 mm | Oversized sport, diver |
Style matters as much as size
The chart above gives a balanced, "safe" range. But three things can push your ideal case size up or down:
- Lug-to-lug over case diameter. A 40 mm dive watch with 50 mm lug-to-lug wears larger than a 42 mm dress watch with 46 mm lug-to-lug. Always check the lug-to-lug spec before buying.
- Thickness. Anything over 13 mm will sit noticeably tall on your wrist. Dress watches are typically 8 to 10 mm, three-hand automatics 10 to 13 mm, and dive watches 13 to 18 mm.
- Dial-to-bezel ratio. Two 40 mm watches can feel very different. A slim bezel makes the dial dominate and the watch wear larger. A thick bezel makes it wear smaller.
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Check authenticityCommon questions
Is 40 mm too big for a 160 mm wrist?
No — 40 mm is within the recommended range for a 160 mm wrist. It's on the larger end of balanced and suits sport, dive, and casual styles. A dress watch at 40 mm on a 160 mm wrist may feel slightly bold but is still acceptable.
What about women's watches?
The same proportion rules apply — wrist circumference is what matters, not gender. Many men wear 36 mm watches and many women wear 40 mm watches. Traditional "ladies" watches are often 28 to 34 mm, but there's no rule stopping you from going larger if the proportions work.
Can I wear an oversized watch?
Yes, if the style calls for it. A 44 mm pilot or dive watch on a 165 mm wrist will overhang slightly at the lugs but is a deliberate look. The rule of thumb is: if the lug-to-lug exceeds your wrist width, the watch will sit awkwardly flat. If you want oversized but comfortable, prioritise shorter lug-to-lug specs.
Does the strap change how a watch fits?
Yes, noticeably. A tapered or suede strap makes a watch feel lighter and smaller. A fat integrated bracelet makes the same case wear larger. Leather straps break in over time, while metal bracelets need precise link removal for the right fit.