What top tube is good for someone that's 5'9 5''i

20.6-20.75 depending on you preferences, i am more or lss like you and i am riding a 20.75 fit wifi, pretty happy with it.

Ride different bikes and see what you like. There's no right or wrong size. I'm 5'9.5 on a 21" randy brown because that geo is what I like. I know taller guys that ride shorter toptubes and shorter guys that ride longer toptubes. It's all preference but I would say 20.75 is a good place to start

I'm 6 and I ride a 21" (and i really want to try bigger) but as tomdom was saying, it´s all about personnal preference.
But with something between 20.75" and 21.25" should be good for you.

20.75 is where it's at. I'm the same height and rode a 20.75 and it was perfect. I'm getting a 20.8 next , slight difference.

im 5'10 ride a 20.5 a 53mm stem and 175 cranks with 8.75 bars and people that ride 21 inches say my bike feels the same or bigger

I am 5'9" and ride a 21" with a 48mm stem

20.75ish

20.5....but then again I'm 5'11 and 20" is the biggest frame I'll ride lol

im 5'9"
I find some "feels longer" despite the shorter TT. now im using eastern grim reaper 20.5" with wtp mad maxx. take into account of geometry of frame+bar+stem combined. i exchanged my 20.8" haro sd v2 (temporarily) with my friend's eastern, and his bar felt horrible . also tried a junglerider indamix 20.5" and it felt longer than the haro 20.8"