When does the endgame start?

https://www.imdb.com/title/tt1630891/?ref_=ttep_ep2
It's a Futurama spoof of the Star Trek: The Motion Picture.

I don't think there's any one pure endgame definition, but you know you are in an endgame if:
-- you want to activate your king.
-- you no longer automatically want the initiative but must calculate whether you want to lose a move or not.
Generally, if the Queens are off the board, I'm thinking endgame.
I don't exactly agree, because I sometimes trade off the queens in the opening or early in the middlegame.

When there is little enough material left on the board that mating attacks are impractical/impossible and the the goal to strive for is queening a pawn to achieve a decisive advantage.

I think endgame starts if all of the next moves needs to be calculated with the highest amount of accuracy because the other ones are losing moves. This is because there is less options where most of the time all of the possible calculations leads to a sharp positions. The best quote to explain the transition between the phases of the game is "In the opening a master should play like a book, in the mid-game he should play like a magician, in the ending he should play like a machine." by Rudolf Spielmann. That is why, you need to calculate well in the endgame because this is the phase of the game which is the most critical if both players strength during this time is equal.

I think endgame starts if all of the next moves needs to be calculated with the highest amount of accuracy because the other ones are losing moves. This is because there is less options where most of the time all of the possible calculations leads to a sharp positions. The best quote to explain the transition between the phases of the game is "In the opening a master should play like a book, in the mid-game he should play like a magician, in the ending he should play like a machine." by Rudolf Spielmann. That is why, you need to calculate well in the endgame because this is the phase of the game which is the most critical if both players strength during this time is equal.
I do not really understand, but I agree about the part where it says "In the opening a master should play like a book, in the mid-game he should play like a magician, in the enidng he should play like a machine.

Does the endgame start after all the pieces are off the board?
Well, I couldn't imagine a game of chess continuing with no pieces on the board! JK
Some players might respond with "when the Queens come off" but this seems to be an overly-simplified definition. There are Queen endgames and the Queens can come off in the early middlegame. A definition that I read somewhere that I really like went something like this:
"The endgame ensues when the safety of the King stops being a central concern and the participation of the King as an active piece becomes an integral part of the game."
Am I the only one replying 14 years late?
Here’s an example of the queens coming off very early:
It’s move five, and the queens are off the board. Does that mean it’s the endgame?

no. it is a queenless middlegame, where white is down a piece but up a pawn with out clear compensation. there's a lot of time before an end game.

There isn't a concrete definition but the end game is characterised as after the game pivots from focussing on tactics for material advantage to tactics with a few pieces remaining, pawn promotion, King activation and a strategy focussed on the inevitable conclusion of the match.
I would say that when a group of pawns or a rook becomes clearly superior than a bishop or knight. What I mean is that in the early parts of the game the bishops and knights are developed and used to attack primarily and sacraficeing rooks is common for middle game checkmate, because rooks are late game pieces, the less material is on the board the rooks feel more and more powerful. Same but a bit different with pawns. They are more frequently used early, but a pawn advantage feels more and more the less pieces are on the board. The last piece like this is the king. In an endgame, a king is a powerful piece while in early and midgame, he needs to hide and be defended.

I always say it starts the moment either player is considering moving their king as an additional fighting piece, rather than just keeping it safe.
Before Avengers: Endgame, there was the series finale of Star Trek: Voyager