An old "rule of thumb" used to be height in inches, divided by 3. Thus my height is 5' 9" and I used to ride a 23" frame. But nowadays go a bit smaller and most are 56cm's. However, my tandem is only a 21" front and with the right seat post and stems, I get more or less the same riding position.
So probably for you, a max of about 22.5", but you would be ok with smaller sizes. Best if you can try before you buy.