I am using a recipe that calls for 4oz chard, center ribs removed. How many leaves do you think that is? I really don't know and don't have a

Stems included:
Really large chard, 4 leaves = 1 lb.
Medium chard, 6 to 12 leaves = 1 lb.
Small chard, 12 or more leaves = 1 lb.

I would probably say the stems (if we are taking out the part in the center of the green as well) takes about 3/4 of the total weight.

I used 4 leaves I think...

It's from this site actually. Quinoa, fava bean, chard burgers. You are right. Probably not so crucial to be exact!!

*Sorry: "your" recipe.

What's you recipe? In many cases, the amount is not crucial--recipes always seem to want to prescribe exact amounts when, in many cases, exact amounts aren't terribly important. I would just buy a healthy bunch. If the bunches you find are small, buy two. And remember not to fret too much ;)