Holdem head up all-in in the dark

[Ghazban]

On various televised TV tourneys, I've seen a point in the headup where, due to the blind sizes + antes, a person is mathematically correct to go all-in regardless of what two cards they have. What kind of pot odds do you need to be getting to make moving all-in regardless of your cards the correct play? I'm sure I've seen the figure before but can't seem to remember it. Thanks.

[tardigrade]

I know if you are in the small blind and completing would take you all-in, then you would go all-in with any two cards. I believe there is a similar situation when you are in the BB and you have <= an additional BB left it is correct to go all-in with any 2.

(EDIT: The necessary pot odds pre-flop are, I think, about 3:1)

[Ghazban]

Thanks for the reply; 3:1 sounds vaguely familiar so that's probably right. Does it change if there are multiple people still to act instead of just one (say, at a final table of 6 instead of final 2)? I don't think it should but I'm not exactly sure how to frame the question mathematically to figure it out.

[Nottom]

[ QUOTE ]
I know if you are in the small blind and completing would take you all-in, then you would go all-in with any two cards. I believe there is a similar situation when you are in the BB and you have <= an additional BB left it is correct to go all-in with any 2.

[/ QUOTE ]

This is basically correct, but you will often see people call with even slightly worse odds. For example, you are in the BB with 36o. Button puts you all-in.

If you have 3-4 BBs you should still probably call unless you are in a bubble-type situation. If you fold, it just puts you in worse shape becasue you will now only have 2-3BBs and be puting up the SB next hand. You basically have no bluffing equitty left so even if push, the BB will call you with anything. if there are antes then the situation is even worse. Basically you call and hope he has overcards and the 70-30 comes down in your favor and doubles you up, and once you have the bigger stack you can play a better short-stack game.

[tardigrade]

I'm sure the number of players at the table is relevant to many situations, but probably not to your blind decisions. The closest thing I've seen to an analysis of it is Sklansky's "Improved System" in TPFAP. But even that is kind of an estimate. It seems in that case, when the blinds are getting up to about 1/4 of your stack it has you going all-in with any two in most situations.