US ring size 7
US size 7 has an inside diameter of approximately 17.3 mm and an inside circumference of 54.4 mm.
Inside diameter17.3 mm
Inside circumference54.4 mm
How to check whether size 7 fits
Measure the inside diameter of a ring that already fits the intended finger. Measure straight across the widest inside point—do not include the metal. Compare that measurement with 17.3 mm.
This is a jewellery-size conversion, not a guarantee of fit. Finger size changes with temperature and time of day; wide bands often need extra room.