Lug-to-lug: the measurement that decides how a watch fits
Lug-to-lug is the distance from the tip of the top lugs to the tip of the bottom lugs of a watch, measured in millimetres. It matters more than case diameter for how a watch fits: if the lug-to-lug is longer than the flat top of your wrist, the lugs overhang and the watch looks and feels too big, whatever its diameter.
Updated
Why diameter isn't enough
Two watches with the same 40 mm diameter can wear very differently. One with short, curved lugs and a 46 mm lug-to-lug may sit neatly on a small wrist; another with long, straight lugs and a 50 mm lug-to-lug may overhang the same wrist. Lug-to-lug, together with case thickness and how much the lugs curve, is what decides fit.
How to measure it
Use a ruler or, better, calipers. Measure in a straight line from the tip of the lugs at 12 o'clock to the tip of the lugs at 6 o'clock. Many brands and reviews list it, but it's worth measuring your own watches: once you know the lug-to-lug of a watch that fits you perfectly, you have a reference for every future purchase.
How to measure your wrist for it
Look at your wrist from above and measure the width of the flat top, from one side to the other, where the watch sits. A watch generally fits best when its lug-to-lug is no longer than that flat area.
A rough guide by wrist size
| Wrist circumference | Lug-to-lug that usually fits |
|---|---|
| 15 cm (6 in) | up to about 46 mm |
| 16.5 cm (6.5 in) | up to about 48 mm |
| 18 cm (7 in) | about 48–50 mm |
| 19 cm (7.5 in) | up to about 52 mm |
| 20 cm (8 in) and over | 52 mm and more |
These are rules of thumb, not rules. Wrist shape matters as much as size (a flat, wide wrist carries more than a round one), and curved lugs, a thin case or a flexible strap can all make a larger watch wear smaller.
Keep a note of your watches' measurements
Recording the lug-to-lug of every watch you own, and noting which ones fit best, makes buying online far less risky. WristLog.app lets you keep lug-to-lug and case measurements with each watch in your collection, and on your wishlist.
Common questions
What is a good lug-to-lug for a 7-inch wrist?
For a 7-inch (about 18 cm) wrist, many people find watches up to around 48–50 mm lug-to-lug fit comfortably. It depends on the shape of your wrist and how the lugs curve.
Is lug-to-lug the same as case size?
No. Case size usually means the diameter across the case, without the crown. Lug-to-lug is the length from the top lugs to the bottom lugs, which is usually longer and more important for fit.
Do curved lugs make a watch wear smaller?
Yes. Lugs that curve down around the wrist reduce overhang, so a watch with curved lugs can wear smaller than its lug-to-lug suggests.
WristLog.app
See it for your own collection.
WristLog.app catalogues your watches from a photo and shows you how you really wear them. Free on iPhone and Android.
