Cuff 1.75 in. (~4.45 cm)
Cuffs add weight to the hem, allowing your trousers to fall nicely. This is important if you're choosing our lightweight/light-midweight fabrics, as it may float about in the absence of a cuff.
However, practical considerations can sometimes give way to sartorial considerations. Cuffs carry with them a certain appeal of elegance, and can flatter you when it's done in the right proportion. If you're around 5'8/1.73m, 1.75inch cuffs is a good starting point.