Inseam length
 

What would be the typical inseam for a person who is 5'9? (Assume the person has normal proportionality...ie. not long-waisted, etc.)

If you buy good enough quality trousers they come unfinished and you don't have to worry about it. But you should know the waist size going in.

I have the waist size. It's just that if I ask my friend for his inseam measurement, it kinda gives away what the present will be.....and I'm buying jeans, not trousers, so I need to know the inseam going in.

Unfortunately, I think this depends on proportions in addition to just height. I am between 5'10" and 5'11", and I need at least a 34" inseam, but my ex was about 6'2" and wore almost the exact same size.

In summary, steal a pair of his pants and check.

If you could check his pants like DBB suggested that would be the best way to go.

That being said, I'm between 5'9 and 5'10 and I usually wear a 30 inch inseam. I've found that shorter lengths than 30 are less commonly available, and since he's someone who doesn't know the length offhand I'm guessing he's not seeking out shorter sizes.

I stole two pairs of his pants, and even put one of them on. The waist said 34 on one pair and 36 on the other. Neither had inseam listed (why I tried one on) and they seemed a little longer than mine. My Levi's were 30s that I had shortened to fit. I had kinda thought 30 would be correct, but thought maybe asking first would be best!

He lives in England, and when I was shopping in the stores, I didn't see any Levi 501s, which is what I plan to get him as a present.

Take a pair of one and compare the waist to the inseam of the other to see how close to 34 or 36 they are and guess the discrepancy (how many inches).

Do you have a tape measurer? That can tell you, too. If you don't have a tape measurer, use a piece of string or something and measure it at home

The seam is the length from the inner thigh that hits the seam of the crotch area down to the bottom hem of the jeans.