When do you consider yourself out of fold equity?

[Bigwig]

Obviously, if you move all-in from the CO and the Button is sitting on QQ, you're usually in a lot of trouble. But it seems to me that the big worry about fold equity comes from the range of hands that the BB or early limpers may call with, since they are often the last to act after you've made your move. With money already in the pot, they're getting significantly better odds to call.

Without limpers, it appears (based on my calculations) that you need at least 5BB to make their call difficult. And, if there are limpers, you need even more.

What do you consider the point where you've lost all fold equity?

And with limpers in the hand, how does this affect your thought process?

It seems to me that the limpers and BB's stack size has to be taken into consideration. Big stacks will obviously have much more freedom to call a with proper odds, if they will only lose something like 25% of their stack if they don't win, and this must be considered if you're going to move in with a 'decent' hand like 55 or KQo when you only have 5BB.

Thoughts?

Thanks.