Rakeback

Rake is the scaled commission fee taken by a cardroom operating a poker game. It is generally 2.5 to 10 percent of the pot in each poker hand, up to a predetermined maximum amount. There are also other non-percentage ways for a casino to take the rake. Some cardrooms will not take a percentage rake in any community card poker game like Texas hold 'em when a hand does not have a flop. This is called "no flop, no drop".

Poker is a player-versus-player game, and the house does not wager against its players (unlike blackjack or roulette), so this fee is the principal mechanism to generate revenues.

It is primarily levied by an establishment that supplies the necessary services for the game to take place. In online poker it covers the various costs of operation such as support, software and personnel. In traditional brick and mortar casinos it is also used to cover the costs involved with providing a dealer (though in many places tips provide the bulk of a dealer's income) for the game, support staff (from servers to supervisors), use of gaming equipment, and the physical building in which the game takes place. The rake in live games is generally higher than for online poker.

To win when playing in poker games where the house takes a cut, a player must not only beat opponents, but also the financial drain of the rake.

There are several ways for the rake to be taken. Most rake is a fixed percentage of the pot, taken on a sliding scale, with a capped maximum amount that can be removed from the pot regardless of pot size. Less frequently, rake is a fixed amount no matter what the size of the pot.

A percentage rake is taken directly from the pot. In a live casino, the dealer manually removes chips from the pot while the hand is being played and sets them aside to be dropped into a secure box after completion of the hand. When playing online, the rake is taken automatically by the game software. Some software shows the rake amount next to a graphical representation of the dealer and takes it incrementally between the rounds of betting, whereas other software programs wait until the entire hand is over and then takes it from the pot total before giving the rest to the winner of the hand. This is the prevalent method of collecting rake in online poker.

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Wikipedia