Five-card stud first appeared during the American Civil War, and became very popular. In recent years, Seven-card stud has become more common, both in casinos and in home games. These two games form the basis of most modern stud poker variations.
The number of betting rounds in a game influences how well the game plays with different betting structures. Games with four or fewer betting rounds, such as five-card stud and Mississippi stud (described below), play well with any structure, and are especially well suited to no limit and pot limit play. Games with more betting rounds are more suited to fixed limit or spread limit. It is common (and recommended) for later betting rounds to have higher limits than earlier ones. For example, a "$5/$10 Seven-card Stud" game in a Nevada casino allows $5 bets for the first two rounds and $10 bets for subsequent rounds. Also common is to make the final round even higher: a "$5/$10/$20" game would allow $20 bets on the last round only. Another common rule is to allow the larger bet on the second round if there is an "open pair" (that is, at least one player's upcards make a pair). Some casinos (typically in California) use the smaller limit on the first three rounds rather than just the first two.
It is a common convention in stud poker to name the betting rounds after the number of cards each player holds when that betting round begins. So the bet that occurs when each player has three cards is called "third card" or "third street", while the bet that occurs when each player has five cards is "fifth street". The final round, regardless of the number of betting rounds, is commonly called the "river" or simply the "end".
Any game can also be changed by adding one or more jokers to the deck to act as wild cards, or by designating certain other cards as wild. Some specific common variations include Low hole card wild, in which each player's lowest-ranking downcard (and all other cards of that same rank) are wild in that player's hand only, and Follow the queen, in which each time a Q is dealt face up to anyone, the next face up card (and all others of that rank) become wild. The usual practice in the latter case is that if a second Q appears among the upcards, the previous wild card loses its status to the new one.
One can also vary any stud game by dealing extra downcards and requiring either that one or more hole cards be discarded at some point in the game or adding a restriction on how many of those hole cards may be played in the final hand. For example, five-card stud can be modified by dealing each player an extra downcard at the start of the game, adding the restriction that each player may only use one of his two downcards in his final hand. This game is called Crocodile stud. Likewise, seven-card stud can be modified by dealing each player three downcards instead of two on the first round, but adding the restriction that a player may use no more than two of those cards in his final hand (called Buffalo stud; if the extra hole card must be discarded after the first betting round, then it is Australian stud). If playing one of these games without the requirement to discard the extra hole card at some time during play, it is recommended as a practical matter to ensure compliance that each player physically discard one hole card immediately before showdown, before revealing the "live" hole cards (so that there can be no confusion about which cards were down).
Variations can be made by eliminating betting rounds, dealing more than one upcard at a time for one or more rounds. For example, Mississippi stud (see below) is basically seven-card stud with the second betting round removed, and the last card dealt face up instead of face down. Further adding an extra hole card as above makes it Murrumbidgee stud.
Games that mix stud-like rounds with community cards are discussed on the community card game page. In general, one can mix upcard rounds with community card rounds in many ways. See in particular Oxford stud on the community card game page.
As mentioned above, seven-card stud is probably the most common form of the game, with most other games being variants of that, although five-card stud is also a basic pattern upon which many variations are built. These games are described on their own page. Most of the games described below started as ad-hoc variants, but they have either become popular enough to have a common name, or else have some unique feature to merit including them here.
Six-card stud is usually played as identical to seven-card stud, except that the last face-up round is removed (Thus it is two down, three up, one down). It can also be played as 1-4-1, where the first betting round occurs after only two cards are dealt (one down and one up). This latter form more closely resembles five-card stud with an extra downcard.
A variation called Alligator stud starts with one hole card and one upcard, followed by a first betting round; then two upcards are dealt to each player followed by a second betting round; then a fourth upcard and betting round, and finally a fifth upcard and betting round. This game plays well at no limit and pot limit. The same game, but with each player initially dealt two downcards and one upcard, and restricted to using only one of his downcards in his final hand, is called Zanetti stud.
Razz is seven-card stud played with ace-to-five low hand values. It is usually played with a bring-in, paid by the player with the highest-ranking upcard on the initial deal (aces are always low cards in Razz, even for the purpose of assigning the bring-in). On the second and subsequent rounds, the player with the lowest exposed hand starts the betting.
Here's a sample Razz deal (suits are omitted here because they are never of consequence in Razz; in London lowball, a flush cannot play as a low hand but otherwise they don't generally matter either). Alice deals each player two downcards and then one upcard: Bob's upcard is a J, Carol is dealt a 3, David an A, and Alice a 4. Bob's J is the high card (David's A is low), so he pays a $1 bring-in. Carol, David, and Alice all call. Now bob is dealt a 9, Carol another 3, David a 4, and Alice a 2. The best low hand showing is now David's 4-A, just beating Alice's 4-2. David bets $1, Alice calls. Bob folds his J-9, and Carol calls (her pair of 3s is the worst hand showing, but there are still many cards to come). Alice now deals Carol an A, David a K, and herself an 8. The low hand showing is now Alice's 8-4-2, so she bets $2. Carol raises $2, and David folds. Alice calls, ending the round. Carol is now dealt a 6, and Alice another 8. Now the lowest hand showing is Carol's 3-3-6-A, a pair of 3s being lower than Alice's pair of 8s. She bets $2 and Alice calls. A final downcard is dealt, Carol again best $2, and Alice calls. Alice reveals that her downcards are 7-J-A, making her lowest five-card hand an 8-7-4-2-A. Carol reveals her downcards to be a 4-6-7, making her lowest five-card hand a 7-6-4-3-A, which wins the pot.
Also known as "seven eight" or "stud eight", eight or better is the most common form of high-low split stud. Played as seven-card stud, but the pot is split between the player with the highest hand and the player with the lowest hand (using the ace-to-five low values). An 8-high hand or lower is required to win low. Betting takes place as if playing standard high-hand stud; that is, low card pays the bring-in, if any, on the first round, and subsequent rounds start the betting with the highest showing poker hand. The showdown is cards speak, that is, there is no declaration for high and low. Each player may choose a different subset of five cards to play for high and low. For example, a player with A-A-8-6-6-4-3 can play a high hand of A-A-6-6-8, and a low hand of 8-6-4-3-A. A player with K-9-8-7-6-5-4 can play a 9-high straight for his high hand, and 8-7-6-5-4 for low (which is the worst possible qualifying low, but it does qualify). A player with K-9-8-7-7-6-5 can play the 9-high straight for high, but cannot play any low hand, because he cannot make an 8-high or lower. If there is no qualifying low hand, high hand takes the entire pot.
This game plays well with a bug or two in the deck.
Mississippi stud was created to make seven-card stud play better at no limit and pot limit, and is slowly becoming popular for that reason. It is also often played with a betting structure more typical of Texas hold'em: fixed limit with the last two rounds double the limit of the first two. The bring-in should be less than the first-round limit.
Initial deal as in standard seven-card stud. After the first betting round, two upcards are dealt to each player, so each now has two down and three up (so unlike standard stud there is no betting on "fourth street"). A second betting round is followed by one more upcard and a third betting round. Finally, the last card is dealt face up, so that each player ends with two downcards and five upcards. Because each player has five upcards on the last round, straights, flushes, and full houses count as "high hand exposed" for the purpose of determining who must bet first. After the seventh street bet there is a normal showdown.
Can also be played with low hands, or high-low split. If three downcards are dealt initially instead of two, with the restriction that no more than two of them can be used in the final hand, this variation is called Murrumbidgee stud.
Various forms of roll your own five-card stud, often with a stripped deck and wild cards, are called Mexican stud, Mexican poker, or Stud loco. One such variant played by the Casino San Pablo in northern California has these rules: 8s, 9s, and 10s are stripped from the deck, and a single joker is added (the deck therefore contains 41 cards). The 7-spot and the J become consecutive, so that 5-6-7-J-Q is a straight. A flush beats a full house (with fewer cards of each suit, they are harder to get). The joker plays as a bug if it is face up, and fully wild if it is face down. The game is played as five-card stud choose-before roll your own. It is usually played with a very high ante, and the high card on the first round pays the bring-in.
The game of Shifting sands is Mexican stud in which each player's hole card (and all others of that rank) are wild for that player only.
Five-card stud played high-low split with an added twist round is called Option alley or five-card option. The game Canadian stud or Sökö is five-card stud with two new hand values added: a four-card straight beats one pair, a four-card flush beats a four-card straight, and two pair beats both of the above.
The term English stud is used ambiguously to refer to several games, including six-card stud played 1-4-1 with a twist (also called six-card option), London lowball, and a seven-card stud game where both sixth street and seventh street are twist rounds.
In the game of seven-card flip, each player is dealt four cards face down, and chooses two of them to turn up. All cards are turned up simultaneously after everyone has chosen. As this point, the game proceeds as if it were standard seven-card stud starting on fourth street.
Kentrel, or "48", is a seven-card stud variation which starts with each player being dealt four downcards. Each player must then discard one, choose one of the remaining three to turn face up (leaving two down and one up as normal), and then proceed as with eight-or-better high-low stud.
The game of Chicago is seven-card stud in which the high hand splits the pot with the player who has the highest-ranking spade "in the hole" (among his downcards).
Several different games played only in low-stakes home games are called Baseball, and generally involve many wild cards (often 3s and 9s), paying the pot for wild cards, being dealt an extra upcard upon receiving a 4, and many other ad-hoc rules (for example, the appearance of the queen of spades is called a "rainout" and ends the hand). These same rules can be applied to no peek[?], in which case the game is called "night baseball".
Cowpie poker is played as seven-card stud until after after the seventh-street bet. All remaining players then split their hands into a five-card hand and a two-card hand. The five-card hand must outrank the two-card hand, and the latter must contain at least one downcard. After the split there is one more betting round and showdown. Upon showdown, the highest five-card hand and the highest two-card hand split the pot. The name of the game is a pun on Pai Gow.
Draft (or "socialist poker") is usually a variant of seven-card stud in which the second and subsequent upcard rounds are dealt this way: for each player remaining, one upcard is dealt to the center of the table (not to any specific player). The player with the worst showing hand gets to choose which of them he will take for his next upcard, then the player with the second-worst showing hand chooses his upcard from those left, and so on, until the player who previously had the best showing hand takes the remaining card. Then betting occurs as normal. In seven-card stud, this makes for three "draft" rounds (the first three cards are dealt normally, as is the final downcard).
Auction is a similar variation in which each upcard round (or possibly just those after the first) begins with an "auction" phase. Instead of dealing each player one upcard, the first card is dealt to the center and all players bid on it; the player who bids the highest amount places that amount into the pot, and then has the right to either keep the auction card as his own upcard, or designate another player who is required to take it as his. After the first card is auctioned off and placed, the remaining players are dealt a random upcard as usual, and betting proceeds as usual. This variation is commonly played as high-low split, so it is common for a player to "purchase" a high card to force it upon an opponent seeking low, for example.