A 4-bet is the second re-raise in a betting round. 4-bets are significantly more common before the flop, but they can happen after the flop as well.
For example, suppose you raise preflop and a player behind you re-raises (aka 3-bets). If the action gets back to you and you re-raise again, that’s a 4-bet.
Want to learn the strategic value of 4-betting in poker? Read this guide:
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