How to determine at what blind level a poker tournament will end
Poker tournaments have blinds that increase over time in order to force action and bring the tournament to an end. As a tournament is not over until one player has all the chips, the mounting blinds are a necessity or the tournament could go on forever. The question is, how high they have to get to end the tournament? Figuring this out is the first step towards building a good tournament blind structure.
I will walk you through the logic I use for determining this end point:
Step 1: Determine total chips in play
If you are playing in a freezeout tournament this equation is very simple:
starting stack x # of players = total chips in play
If you are planning a rebuy tournament it becomes more complex because you don't know prior to the tournament how many rebuys and addons you will have. So You must make estimations on these numbers. These estimates have to take into account; how long is the rebuy period, how many rebuys/addons has this group taken in the past, how high is the buy-in compared to the bankrolls of the players in the tournament, etc. This is more an art than a science but as you gain a little experience it becomes easier. As a minimum for a rebuy tournament I count at least one rebuy and addon per participant. But for some groups, this may be a very low estimate.
If rebuys and addons buy you the same out of chips as the starting stack, as is often the case you can calculate the total chips as follows:
starting stack x (# of players + estimated number of rebuys + estimated number of addons) = total chips in play
or if you want rebuys and addons to buy an amount of chips different than the starting stack then you calculate as follows:
(starting stack x # of players + (rebuy chips x estimated number of rebuys) + (addon chips x estimated number of addons) = total chips in play
Step 2: Determine final blind level
Take your total chips in play and divide by 20 and this gives you an estimate of your final big blind level. It is impossible to determine the exact end of a tournament because a lot depends on the style of play of the finalists and the way the cards fall but this has proved to be a fairly accurate predictor.
To understand the reasoning behind choosing this number, we need to understand what conditions need to be present for a tournament to end.
Typically a tournament ends after a tournament gets down to heads-up (2 players remaining). If we make the assumption that the 2 players have equal chips we can divide the total chips by 2 to get the chips that one of the players would have. Often this is not the case and there is a chip discrepancy between the 2 players but this is a conservative way of estimating.
Then we know that when a player gets down to 10 big blinds their options are limited and it is almost all-in or fold mode. So, it is often at this point where the players will be getting all their chips in the middle. So after dividing by 2 to get one player's stack we divide that by 10 to get the estimated big blind for the end of the tournament. (Dividing by 20 is the same as dividing by 2 and then by 10)