Nut advantage means holding more of the very top hands — sets, straights, two pair — on a given board than your opponent. It is narrower than range advantage, and it is what decides how big you can bet.
Bet size follows the nuts. A player who can hold the best hands while the opponent cannot may bet big and even overbet, since villain has nothing that wants to play a big pot. A player whose range has the equity edge but not the nut edge can bet small at most, because a big bet gets raised by exactly the hands he lacks.
The two advantages usually come together on high boards and come apart on low, connected ones. There the big blind’s defending range — suited connectors, small pairs, suited aces — holds its share of the straights and two pairs, while the button’s extra equity sits in overpairs and big cards that are only one pair. Nut advantage is also what makes a value overbet possible later in the hand: when villain’s line has capped his range and you hold the top of what is possible, a big size wins the most from the hands that cannot fold. Reading equity alone misses this: a range that can be raised off its overpairs is not a range that wants to bet.
Worked example
FAQ
What is the difference between range advantage and nut advantage?
Range advantage is about total equity: whose whole range is stronger on average. Nut advantage is about the very top: who holds more sets, straights and two pairs. You can have the first without the second, as the button does on 6-5-4.
Why does nut advantage matter for bet sizing?
Because big bets get raised by the hands you lack. With the nut edge you can bet big and even overbet; with only an equity edge, a small bet is the most you can make without being raised off your one-pair hands.