This question comes up all the time. Like many questions, there is no good, one size fits all, answer, although there are many bad ones.

We simply cannot judge what another person thinks is possible, particularly with the help of an opponent.

Ultimately life is short and many games reach a point where it would be better to start another. The one answer I always think is bad is "I do not resign because I like to work on my endgame". You need to recognize that you are not getting much practice if your opponent has 40 pts to spend in the endgame.

My answer is related to what I think is the wrong answer above. Don't resign when you cannot win in some absolute if everyone was a 9 dan sense, resign when you are no longer trying to win. I have no problem with trying to live in a territory where life should be impossible, if living would win the game.

I do have a problem with losing 30 minutes of my life while you try to make a 30 pt loss only a 25 pt one.

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My days of not taking you seriously are certainly coming to a middle

This perfectly sums up my feelings too

It also depends what/where the game is. I will resign earlier in a friendly cafe game than a competitive tournament game.

What about resigning early or later if you play against a strong computer opponent? What goes into that decision. Is there a different motivation factor in determining when to resign if you're either playing another human beling or computer software?

If it's a computer, just resign whenever. You won't hurt its feelings.

Maybe what I meant is...by how many points behind should one resign?

how about when there are not enough points left to come from behind and win?

What about 20 - 60 points behind?

I may be misjudging, but based on some of the questions you've asked, you're still at a level where, first, you have no idea whether you're 60 points behind and second, could easily see a 60 point swing in the score over 10 moves.

How far behind you should be when you resign depends on how strong you are. Last week I thought I was hopelessly behind after a blunder and counted; it turned out I was only 5-10 points behind. (then I blundered again, but that's a different story.)

Another answer to a good time to resign is when your opponent asks you to do so by playing a super-slow safe defensive move (or A19 if he's feeling cheeky) as a signal that he's plenty ahead and by fixing that last one bit of bad aji it's game over even with suboptimal moves, such as my c3 in http://www.online-go.com/games/board.php?boardID=347746.

What about when playing 9x9 games? Do you "play out" the entire board and not bothering to resign? By pointing out the smaller board size makes me realize the best indicator of when to resign is not counting but figuring out that you can't surround your opponents stones. But this is a harder judgement to make on a 19x19 goban. Would it be better to think of the 19x19 board as a combination of 4 9x9 grids and thinking of them in 9x9 terms rather than one large 19x19 board?

No

not sure what this means. It is 100% possible to win on 9x9 without surrounding your opponents stones.

you should switch to playing with a simplified version of Chinese rules -- that way you can simply say, the one with the most stones on the board wins. From that, you can get a better picture of when to resign.

You shouldn't be spending time worrying about whether to resign or not. Resigning is what you do when you know you've lost, so if you don't know you've lost, don't resign. Thinking about it any harder than that is wasting time you could have spent thinking about other things.

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We don't know who we are; we don't know where we are.
Each of us woke up one moment and here we were in the darkness.
We're nameless things with no memory; no knowledge of what went before,
No understanding of what is now, no knowledge of what will be.

But isn't one of the skills of Go is reading the board correctly and assuming you've made a mistake or a series of mistakes...you'd know its time to resign? For example, in regular chess...there are games that I know I've won but get annoyed I have to "prove it" by playing out the rest of the game to win the point. But whenever I'm losing a chess match...I don't resist uselessly knowing it's pointless to continue. I'd resign as soon as I see I can't win and my opponent won't make any mistakes bringing home the point.

In the games I've seen on the Go server the losing player ususally resigns before the opponent "proves" the point by filling out the rest of the board with stones. On 9x9 games I've played against the computer...I immediately resign if it's able to capture a group of stones since it's nearly impossible to come back from this on such a small board. But a 13x13 or 19x19 the dynamic is different so therefore there has to be another way of figuring out one's hopelessness in continuing the struggle. So I think this job of determining when it's proper to resign is actually harder in 19x19 games than with smaller boards.

From the way you write about the game, I conclude that it's too early in your development as a go player to be worried. If you play with a teacher, they may indicate if you are playing out hopeless positions. Otherwise, don't worry. You'll be stronger soon, and it will be clearer.

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Occupy Babel!

Counting is a skill in Go; resigning isn't. The purpose of counting (or any other type of assessment of your overall position) shouldn't be so you can say "Oh, I lost :(", it should be so that you can see how you are doing and make a plan to win. If you're ahead by a lot, play safely and don't start needless fights. If you're behind, try to make the game complicated. If you have a lot of influence, try to attack your opponent in order to make the best use of it, etc.

Resigning comes into play when you are able to assess the situation and determine that you cannot come back. If you don't know whether you can come back or not, then you don't know for certain that you've lost yet, so obviously you shouldn't resign.

_________________
We don't know who we are; we don't know where we are.
Each of us woke up one moment and here we were in the darkness.
We're nameless things with no memory; no knowledge of what went before,
No understanding of what is now, no knowledge of what will be.

You are, of course, much stronger than I, and have won the right to say things like this. And your observation that tight endgames are played more aggressively is apt. But if I said "don't waste my time, I'm winning by 25 points," you would have every right to call me arrogant... I've lost 25 points in the endgame more than once, and I'm sure it will happen again. By the same token, if I want to try to get back 25 points in the endgame, I hope my opponent will be understanding. If it turns out I only get five points back, well, can't win them all.

Furthermore, if in an even or properly handicapped game I have been dominating for the first 150 moves, it is perfectly reasonable for my opponent to assume that the reason we are evenly matched is my weak endgame, rather than my aggressive sandbagging or my Lance-quality pharmaceuticals.

Go is about respecting your opponent and yourself. You should continue the game as long as the game's still enjoyable for both of you. Once a game is clearly lost continuing to play is imposing yourself upon your opponent and doing disrespect to both of you. As long as there's still some fight left the game should be fun to continue. Try your best and then resign when you've exhausted all the reasonable opportunities to turn the tables.