What size watch should I get for a 7-inch wrist?

Look for a lug-to-lug of about 51 mm or less. Most watches that fit a 7-inch wrist ideally have a 39–41 mm case, but check lug-to-lug rather than diameter.

Is a 40 mm watch too big for a 6.5-inch wrist?

Often not. It depends on the lug-to-lug: a 40 mm watch under about 47 mm lug-to-lug fits a 6.5-inch wrist well, while one with long lugs can overhang.

Watch Size Chart by Wrist Size (Lug-to-Lug & Case Size)

Watch size chart by wrist size

Find your wrist size, then read across: the largest lug-to-lug that still fits, and the case sizes of the watches that fit it best. The case-size column comes from the watches in the almanac that grade as an ideal fit, so it updates as we measure more.

Wrist	Flat width	Max lug-to-lug	Typical case size	Watches
5.5"14 cm	43.3 mm	39.3 mm	28–36 mm	6
5.75"14.6 cm	45.3 mm	41.3 mm	31–36 mm	7
6"15.2 cm	47.2 mm	43.2 mm	34–36 mm	14
6.25"15.9 cm	49.2 mm	45.2 mm	36–39 mm	48
6.5"16.5 cm	51.2 mm	47.2 mm	38–40 mm	116
6.75"17.1 cm	53.1 mm	49.1 mm	39–41 mm	173
7"17.8 cm	55.1 mm	51.1 mm	39–41 mm	197
7.25"18.4 cm	57.1 mm	53.1 mm	39–42 mm	204
7.5"19.1 cm	59.1 mm	55.1 mm	39–42 mm	188
7.75"19.7 cm	61 mm	57 mm	40–42 mm	158
8"20.3 cm	63 mm	59 mm	40–43 mm	96
8.25"21 cm	65 mm	61 mm	41–43 mm	44
8.5"21.6 cm	66.9 mm	62.9 mm	42–44 mm	20

How to read the chart

Flat width is our estimate of the flat top of the wrist, 31% of its circumference. Max lug-to-lug leaves about 2 mm of wrist beyond each lug, which is where a watch stops looking oversized. Typical case size is the middle half of case diameters among the watches that fit that wrist ideally; on a 7-inch wrist that's 39–41 mm.

Case size is a rough guide only. Watches with short lugs wear smaller than their diameter and long-lugged ones wear larger, which is why the fit finder grades on lug-to-lug.

Measure, don't guess

If you don't know your wrist size, measuring it takes two minutes. Not sure where you fall? See the average wrist sizes for men and women.

Questions

What size watch should I get for a 7-inch wrist?: Look for a lug-to-lug of about 51 mm or less. Most watches that fit a 7-inch wrist ideally have a 39–41 mm case, but check lug-to-lug rather than diameter.
Is a 40 mm watch too big for a 6.5-inch wrist?: Often not. It depends on the lug-to-lug: a 40 mm watch under about 47 mm lug-to-lug fits a 6.5-inch wrist well, while one with long lugs can overhang.