Knight or Bishop better?

White vs Black = Better Percentage (with extra material for Black + (X))
Q + R + K vs K + (X) = 95%
Q + B + K vs K + (X) = 85%
Q + P + K vs K + (X) = 90% (Queen + Pawn)
B + B + K vs K + (X) = 75% (Pair of Bishops)
Q + N + K vs K + (X) = 75%
R + B + K vs K + (X) = 60%
R + P + K vs K + (X) = 65% (Rook + Pawn)
R + N + K vs K + (X) = 50%
B + P + K vs K + (X) = 50% (Bishop + Pawn)
N + N + K vs K + (X) = 40% (Pair of Knights)
B + N + K vs K + (X) = 35%
N + P + K vs K + (X) = 30% (Knight + Pawn)

White vs Black = Better Percentage (with extra material for Black + (X) + (X))
Q + R + K vs K + (X) + (X) = 90%
Q + B + K vs K + (X) + (X) = 80%
Q + P + K vs K + (X) + (X) = 85% (Queen + Pawn)
B + B + K vs K + (X) + (X) = 65% (Pair of Bishops)
Q + N + K vs K + (X) + (X) = 65%
R + B + K vs K + (X) + (X) = 50%
R + P + K vs K + (X) + (X) = 55% (Rook + Pawn)
R + N + K vs K + (X) + (X) = 40%
B + P + K vs K + (X) + (X) = 45% (Bishop + Pawn)
N + N + K vs K + (X) + (X) = 30% (Pair of Knights) I have never checkmated with this combination.
B + N + K vs K + (X) + (X) = 25%
N + P + K vs K + (X) + (X) = 20% (Knight + Pawn) I have checkmated with this combination.

Black still faces a significant challenge even with a material count that is similar (3 pieces on each side).
The advantage of two extra pieces makes it harder for White to deliver a checkmate.

Q + K vs K + N + B (with fortress) = 0% Checkmate for White (Draw)

Bishops and knights are equal in points but who is better is depend on position.

i like bishops more though due to its long range

Remove the white pawns and replace them with Bishops.
Remove the black pawns and replace them for knights.
White will checkmate black in 10 moves.
I made a study with that setup.

If it was the opposite, White would not win black in 10 moves.
What is constant is the player that had the bishops had a few centipawn advantages over the knights.

since White has the initiative, they can attack the weakest square immediately. So it's all about timing. Bishops cover 4 squares around it. Knights cover none. It all depends how we compare the position and their reach. Even in an empty chessboard. Play a knight in a corner and they have 2 squares to move too. Place a bishop in the same spot and it has 7 squares it can reach.
Place both of them in the center. The knight has 4 (vertically) + 4 (horizontally)= 8 squares it can reach.
A bishop has an X that extends to lucky 13 other squares.

The only time a knight is better than a bishop is when you have a pawn and you can force the opponent out of the corner to let the pawn promote. The bishop can only do that if the promotion square matches the color of the bishop.

Count the legal moves of each piece. Compare which one has the potential to be useful even in the end game. See the horizon and guess if it's going to be good later.

Bishops are snipers, Knights are king defenders. Are we trying to compare who should be paid more?

@Toscani said in #24:

The only time a knight is better than a bishop is when you have a pawn and you can force the opponent out of the corner to let the pawn promote.
Ever heard about the "bad bishop vs good knight" concept?

https://youtu.be/5-Q3-xduqwg?si=RBTPd4amzToWbFkU

https://www.chessgames.com/perl/chessgame?gid=1032072 [Event "23rd Ch Moscow"] [Date "1943.??.??"] [Result "0-1"] [White "Victor Liublinsky"] [Black "Mikhail Botvinnik"] [ECO "C77"] 1 e4 e5 2 Nf3 Nc6 3 Bb5 a6 4 Ba4 Nf6 5 Bxc6 bxc6 6 Nc3 d6 7 d4 Nd7 8 dxe5 dxe5 9 O-O Bd6 10 Ne2 O-O 11 Ng3 Rb8 12 b3 Re8 13 Be3 g6 14 c3 a5 15 Qc2 Qe7 16 Rfd1 Nc5 17 Ne1 Ne6 18 Nd3 Nf4 19 f3 Ba6 20 c4 c5 21 Qd2 Nxd3 22 Qxd3 Red8 23 Ne2 c6 24 Nc3 Bc7 25 Qc2 Rd4 26 Ne2 ...
"... [26 Ne2 is a] faulty appraisal. White decides that it will be better to part with his knight rather than his bishop in exchange for the intruding rook, but the reverse is true. In these half-closed positions the knight is generally stronger than the bishop. By 26 Bxd4 cxd4 27 Na4, followed by 28 Nb2, the white knight could be brought to the blockade square d3, from where it would develop great activity. ..." - Euwe/Nunn (1997)

for me its bishop