While our watches reflect our own personal taste and style, most of the time we do all want a watch that is proportional to the wrist, as these tend to suit each individual the best. Knowing which watch size works though is not completely straightforward, as watch hand sizes vary considerably even among similar styles.
Thankfully, there is a relatively simple approach you can take that looks at watch diameter v wrist size, so to ensure you always get a good watch size, here's how it works.
If you have a larger wrist, a larger watch will look in proportion to your wrist and hand, while a smaller one will look like it doesn't really fit properly. If you have a smaller wrist, a watch that is too big tends to look garish, and it can send out entirely the wrong message. The key to getting a watch that looks right on your wrist then, is to know your wrist size.
Take a tape measure and wrap it around your wrist to measure the circumference. Once you have that, you can then find a range of good watch sizes that will work for you. Beginning with men, if you have a wrist size of between six and seven inches, then a watch case of between thirty-eight- and forty-two-millimeters diameter will offer the best proportions. If your wrist is larger than seven inches, then a watch case diameter of between forty-four and forty-six-millimeters is the ideal size.
For women with smaller wrists at between five and six inches in circumference, watches of between twenty-two and twenty-eight-millimeters in diameter is perfect. Those with slightly larger wrists of six to seven inches will find a watch diameter of twenty-eight-millimeters to thirty-four-millimeters offers the best proportions.
However, these are only guidelines, and the ultimate answer to what size watch for a 7-inch wrist or any other size, is what you think looks best on you.