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Inchess, arelative value (orpoint value) is a numerical value conventionally assigned to eachpiece. Piece valuations have no role in therules of chess but are useful as an aid to evaluating an exchange of pieces.
The best-known system assigns 1 point to apawn, 3 points to aknight orbishop, 5 points to arook and 9 points to thequeen. For instance,sacrificing a knight or bishop under such an evaluation can still be considered a fairexchange if one can ensure the capture of three or more pawns in return. But valuation systems provide only a rough guide; a piece's true value can vary significantly depending on its board position relative to a player's other pieces and the opponent's pieces.
Piece values exist because calculating to checkmate in most positions is beyond even top computers. Thus, players aim primarily to create a material advantage; to pursue this goal, it is normally helpful to quantitatively approximate the strength of an army of pieces. Such piece values are valid for, and conceptually averaged over, tactically "quiet" positions where immediate tactical gain of material will not happen.[1]
The following table is the most common assignment of point values.[2][3][4][5][6]
The oldest derivation of the standard values is due to the Modenese School (Ercole del Rio,Giambattista Lolli, andDomenico Lorenzo Ponziani) in the 18th century[7] and is partially based on the earlier work ofPietro Carrera.[8] The value of theking is undefined as it cannot be captured or traded during the course of the game.Chess engines usually assign the king an arbitrary large value, such as 200 points or more, to indicate that loss of the king due to checkmate trumps all other considerations.[9] During theendgame, as there is less danger ofcheckmate, the king will often assume a more active role. It is better at defending nearby pieces and pawns than the knight is and better at attacking them than the bishop is.[10] Overall, this makes the king more powerful than a minor piece but less powerful than a rook, so its fighting value is about four points.[11][12]
This system has some shortcomings. Combinations of pieces are not always worth the sum of their parts; for instance, two bishops on opposite colours are usually more valuable than a bishop and a knight, and threeminor pieces (nine points) are often slightly stronger than two rooks (ten points) or a queen (nine points).[13][14] Chess-variant theoristRalph Betza identified the 'leveling effect', which reduces stronger pieces' value in the presence of opponent weaker pieces, as the latter interdict access to part of the board for the former to prevent the value difference from evaporating by 1-for-1 trading. This effect causes three queens to badly lose to seven knights (when both start behind a wall of pawns), even though three times nine is six more than seven times three.[15][1] In a less exotic case, trading rooks in the presence of a queen-vs-3-minors imbalance favours the player with the queen, as the rooks hinder the movement of the queen more than of the minor pieces. Adding piece values is thus a first approximation, because piece cooperation must also be considered (e.g. opposite-coloured bishops cooperate very well) alongside each piece's mobility (e.g. a short-range piece far from the action on a large board is almost worthless).[1]
The evaluation of the pieces depends on many parameters.Edward Lasker wrote, "It is difficult to compare the relative value of different pieces, as so much depends on the peculiarities of the position". Nevertheless, he valued the bishop and knight (minor pieces) equally,[a] the rook a minor piece plus one or two pawns, and the queen three minor pieces or two rooks.[16]Kaufman suggests the following values in themiddlegame:
Paired bishops are worth 7.5 pawns—half a pawn more than the values of the bishops combined. Although it would be a very theoretical situation, there is no such bonus for a pair of same-coloured bishops. Per investigations by H. G. Muller, three light-squared bishops and one dark-squared bishop would receive only a 0.5-point bonus, while two on each colour would receive a 1-point bonus. More imbalanced combinations like 3:0 or 4:0 were not tested.[17] The position of each piece also makes a significant difference: pawns near the edges are worth less than those near the centre, pawns close to promotion are worth far more,[1] pieces controlling the centre are worth more than average, trapped pieces (such asbad bishops) are worth less, etc.
Although the 1-3-3-5-9 system of point totals is the most commonly used, many other systems of valuing pieces have been proposed. Several systems treat the bishop as slightly more powerful than a knight.[18][19]
Note: Where a value for the king is given, this is used when considering piece development, its power in the endgame, etc.
|  |  |  |  |  | Source | Date | Comment | 
|---|---|---|---|---|---|---|---|
| 3.1 | 3.3 | 5.0 | 7.9 | 2.2 | Sarratt[verification needed] | 1813 | (rounded)[b][c] | 
| 3.05 | 3.50 | 5.48 | 9.94 | Philidor | 1817 | Staunton (1847) agrees;[d] | |
| 3 | 3 | 5 | 10 | Pratt | early 19th century | [21] | |
| 3.5 | 3.5 | 5.7 | 10.3 | Bilguer | 1843 | (rounded)[21][e] | |
| 3 | 3 | 5 | 9–10 | 4 | Lasker | 1934 | [22][f] | 
| 3.5 | 3.5 | 5.5 | 10 | Euwe | 1944 | [23] | |
| 3.5 | 3.5 | 5.0 | 8.5 | 4 | Lasker | 1947 | (rounded)[24][g][h] | 
| 3 | 3+ | 5 | 9 | Horowitz | 1951 | [25][i][26] | |
| 3 | 3.5 | 5 | 10 | Turing | 1953 | [27] | |
| 3.5 | 3.5–3.75 | 5 | 10 | 4 | Evans | 1958 | [28][j][k] | 
| 3.5 | 3.5 | 5 | 9.5 | Styeklov (early Soviet chess program) | 1961 | [29][30] | |
| 3 | 3.25 | 5 | 9 | ∞ | Fischer | 1972 | [31][l] | 
| 3 | 3 | 4.25 | 8.5 | European Committee on Computer Chess, Euwe | 1970s | [32] | |
| 3 | 3.15 | 4.5 | 9 | Kasparov | 1986 | [33] | |
| 3 | 3 | 5 | 9–10 | Soviet chess encyclopedia | 1990 | [21][m] | |
| 4 | 3.5 | 7 | 13.5 | 4 | used by a computer[which?] | 1992 | [21][n] | 
| 3.20 | 3.33 | 5.10 | 8.80 | Berliner | 1999 | [34][o] | |
| 3.25 | 3.25 | 5 | 9.75 | Kaufman | 1999 | [p][35][q] | |
| 3.5 | 3.5 | 5 | 9 | Kurzdorfer | 2003 | [36] | |
| 3 | 3 | 4.5 | 9 | another popular system[which?] | 2004 | [37] | |
| 2.4 | 4.0 | 6.4 | 10.4 | 3.0 | Yevgeny Gik | 2004 | [38][full citation needed][s] | 
| 3.5 | 3.5 | 5.25 | 10 | Kaufman | 2011 | [39][t][p][u] | |
| 3.05 | 3.33 | 5.63 | 9.5 | AlphaZero | 2020 | [40] | |
| 3.25 | 3.5 | 5 | 9.75 | Kaufman | 2022 | [41][v] | 
Larry Kaufman in 2021 gives a more detailed system based on his experience working with chess engines, depending on the presence or absence of queens. He uses "middlegame" to mean positions where both queens are on the board, "threshold" for positions where there is an imbalance (one queen versus none, or two queens versus one), and "endgame" for positions without queens. (Kaufman did not give the queen's value in the middlegame or endgame cases, since in these cases both sides have the same number of queens and their values cancel.)[42]
| Game phase |  |  |  |   |  |  |  |  | Comments | 
|---|---|---|---|---|---|---|---|---|---|
| pawn | knight | bishop | paired bishop bonus | firstrook | second rook | queen | second queen | ||
| Middlegame | 0.8 | 3.2 | 3.3 | +0.3 | 4.7 | 4.5 | – | – | (both sides have a queen) | 
| Threshold | 0.9 | 3.2 | 3.3 | +0.4 | 4.8 | 4.9 | 9.4 | 8.7 | (one queen vs. zero, or two queens vs. one) | 
| Endgame | 1.0 | 3.2 | 3.3 | +0.5 | 5.3 | 5.0 | – | – | (no queens) | 
The file of a pawn is also important, because this cannot change except by capture. According to Kaufman, the difference is small in the endgame (when queens are absent), but substantial in the middlegame (when queens are present):[42]
| centre pawn | bishop pawn | knight pawn | rook pawn | 
| 1 | 0.95 | 0.85 | 0.7 | 
In conclusion:[42]
In the endgame:[42]
In the threshold case (queen versus other pieces):[42]
In the middlegame case:[42]
The above is written for around ten pawns on the board (a typical number); the rooks' value decreases as pawns are added and increases as pawns are removed.[42]
Finally, Kaufman proposes a simplified version that avoids decimals: use the traditional values P = 1, N = 3, B = 3+, and R = 5 with queens off the board, but use P = 1, N = 4, B = 4+, R = 6, Q = 11 when at least one player has a queen. The point is that two minor pieces equal a rook and two pawns with queens on the board, but only a rook and one pawn without queens.[42]
WorldCorrespondence Chess ChampionHans Berliner gives the following valuations, based on experience and computer experiments:
There are adjustments for therank andfile of a pawn and adjustments for the pieces depending on howopen orclosed the position is. Bishops, rooks, and queens gain up to 10% more value in open positions and lose up to 20% in closed positions. Knights gain up to 50% in closed positions and lose up to 30% in the corners and edges. The value of agood bishop may be 10% higher than that of abad bishop.[43]
| a | b | c | d | e | f | g | h | ||
| 8 |              | 8 | |||||||
| 7 | 7 | ||||||||
| 6 | 6 | ||||||||
| 5 | 5 | ||||||||
| 4 | 4 | ||||||||
| 3 | 3 | ||||||||
| 2 | 2 | ||||||||
| 1 | 1 | ||||||||
| a | b | c | d | e | f | g | h | ||
There are different types ofdoubled pawns (see diagram. White's doubled pawns on the b-file are the best situation in the diagram, since advancing the pawns and exchanging can get them un-doubled and mobile. The doubled b-file pawn is worth 0.75 points. If the black pawn on a6 were on c6, it would not be possible to dissolve the doubled pawn, and it would be worth only 0.5 points. The doubled pawn on f2 is worth about 0.5 points. The second white pawn on the h-file is worth only 0.33 points, and additional pawns on the file would be worth only 0.2 points.[44]
| Rank | Isolated | Connected | Passed | Passed & connected | 
|---|---|---|---|---|
| 4 | 1.05 | 1.15 | 1.30 | 1.55 | 
| 5 | 1.30 | 1.35 | 1.55 | 2.3 | 
| 6 | 2.1 | — | — | 3.5 | 
| 
 | 
 | 
As already noted when the standard values were first formulated,[45] pieces' relative strength change as a game progresses to theendgame. Pawns gain value as their path to promotion becomes clear, and strategy begins to revolve around either defending or capturing them before they can promote. Knights lose value as their unique mobility becomes a detriment to crossing an empty board. Rooks and (to a lesser extent) bishops gain value as lines of movement and attack are less obstructed. Queens slightly lose value as their high mobility becomes less proportionally useful when there are fewer pieces to attack and defend. Some examples follow.
C.J.S. Purdy gaveminor pieces a value of3+1⁄2 points in the opening and middlegame but 3 points in the endgame.[49]
There are shortcomings of giving each type of piece a single, static value.
| a | b | c | d | e | f | g | h | ||
| 8 |                                | 8 | |||||||
| 7 | 7 | ||||||||
| 6 | 6 | ||||||||
| 5 | 5 | ||||||||
| 4 | 4 | ||||||||
| 3 | 3 | ||||||||
| 2 | 2 | ||||||||
| 1 | 1 | ||||||||
| a | b | c | d | e | f | g | h | ||
Positions in which a bishop and knight can be exchanged for a rook and pawn are fairly common (see diagram). In this position, White should not do that, e.g.:
This seems like an even exchange (6 points for 6 points), but it is not, as two minor pieces are better than a rook and pawn in themiddlegame.[52]
In most openings, two minor pieces are better than a rook and pawn and are usually at least as good as a rook and two pawns until the position is greatly simplified (i.e. late middlegame or endgame). Minor pieces get into play earlier than rooks, and they coordinate better, especially when there are many pieces and pawns on the board. On the other hand, rooks are usually blocked by pawns until later in the game.[53]Pachman also notes thatpaired bishops are almost always better than a rook and pawn.[54]
| a | b | c | d | e | f | g | h | ||
| 8 |                           | 8 | |||||||
| 7 | 7 | ||||||||
| 6 | 6 | ||||||||
| 5 | 5 | ||||||||
| 4 | 4 | ||||||||
| 3 | 3 | ||||||||
| 2 | 2 | ||||||||
| 1 | 1 | ||||||||
| a | b | c | d | e | f | g | h | ||
In this position, White has exchanged a queen and a pawn (10 points) for three minor pieces (9 points). White is better because three minor pieces are usually better than a queen because of their greater mobility, and Black's extra pawn is not important enough to change the situation.[55] Three minor pieces are almost as strong as two rooks.[56]
| a | b | c | d | e | f | g | h | ||
| 8 |                               | 8 | |||||||
| 7 | 7 | ||||||||
| 6 | 6 | ||||||||
| 5 | 5 | ||||||||
| 4 | 4 | ||||||||
| 3 | 3 | ||||||||
| 2 | 2 | ||||||||
| 1 | 1 | ||||||||
| a | b | c | d | e | f | g | h | ||
In this position, Black is ahead in material, but White is better. White's queenside is completely defended, and Black's additional queen has no target; additionally, White is much more active than Black and can gradually build up pressure on Black's weak kingside.
Infairy chess, in general, the approximate value,, incentipawns of a short-range leaper with moves on an8 × 8 board is The quadratic term reflects the possibility of cooperation between moves.[1]
If pieces are asymmetrical, moves going forward are about twice as valuable as move going sideways or backward, presumably because enemy pieces can generally be found in the forward direction. Similarly, capturing moves are usually twice as valuable as noncapturing moves (of relevance for pieces that do not capture the same way they move). There also seems to be significant value in reaching different squares (e.g. ignoring the board edges, a king and knight both have eight moves, but in one or two moves a knight can reach 40 squares whereas a king can reach only 24). It is also valuable for a piece to have moves to squares that are orthogonally adjacent, as this enables it to wipe out lone passed pawns (and also checkmate the king, but this is less important as usually enough pawns survive to the late endgame to achieve checkmate via promotion). As many games are decided by promotion, the effectiveness of a piece in opposing or supporting pawns is a major part of its value.[1]
An unexpected result from empirical computer studies is that theprincess (a bishop-knight compound) andempress (a rook-knight compound) have almost exactly the same value, even though the lone rook is two pawns stronger than the lone bishop. The empress is about0.5 pawns weaker than the queen, and the princess0.75 pawns weaker than the queen. This does not appear to have much to do with the bishop's colourboundedness being masked in the compound, because adding a non-capturing backward step turns out to benefit the bishop about as much as the knight; and it also does not have much to do with the bishop's lack of mating potential being so masked, because adding a backward step (capturing and non-capturing) to the bishop benefits it about as much as adding such a step to the knight as well. A more likely explanation seems to be the large number of orthogonal contacts in the move pattern of the princess, with 16 such contacts for the princess compared to 8 for the empress and queen each: such orthogonal contacts would explain why even incylindrical chess, the rook is still stronger than the bishop even though they now have the same mobility. This makes the princess extremely good at annihilating pawn chains, because it can attack a pawn as well as the square in front of it.[1]
Lasker adjusts some of these depending on the starting positions, with pawns nearer the centre, with bishops and rooks on thekingside, being worth more:
Completely revised and updated for the 21st century
{{cite book}}:ISBN / Date incompatibility (help){{cite book}}:ISBN / Date incompatibility (help)Teaching the rudiments of the game, and giving an analysis of all the recognized openings.