What to raise pf on the button

[Raiseren1]

This is an example. Imagine everybody folded to you on the button, and the blinds are unknown. What do we raise with here?

Example 2. Same situation, but the blinds are tight (vpip less than 25%)?

Example 3: Same situation, but the blinds are LAG (but not maniacs).?

[kapw7]

VPIP is not very accurate in this situation. Use "fold BB(SB) to steal".
You also need to consider the blind structure. Assume it's 1:2 SB:BB

If BOTH blinds are tight then you can raise any 2 I guess if they both fold ~60% of times.

This is somewhat rare but I would still go for it if they are straightforward post flop, ie they won't put a lot of buff raises or make very loose calls. For example even if the BB calls 100% on the blind but folds 60% on the flop cbet then you still make a profit with any 2.

Actually have a look at HFAP at the HU section where there is a good basic discussion.

[Raiseren1]

Ok. But what to raise on the button against to unknown? I think I might be to lose. E.g. I raise with K4o, thinking I have an advance with an average hand in position with dead money in the pot. Is this the correct play?