If you decide to bet, it is very important to wager the right amount. The most important thing to know is that the size of a bet is measured relative to the pot: all players should be aware of how big the pot is so that they know how much they stand to win for continuing with their hand.
If you bet $10 into a pot that only stands at $5, you are risking a lot to gain a little. It is a huge bet. On the other hand, if you bet $100 into a pot that is already at $1,000, the bet is tiny compared with the pot.
Although fashions in bet sizing are always changing, and advanced players have different reasons for betting different sizes, the following are widely accepted definitions:
This applies in cash games or tournaments. In the former, the pot will be real money, while in the latter it will comprise tournament chips. But the general guidelines apply in both instances.
The size you want to bet will always depend on the specific situation, but typically players might want to make small bets on a dry board (ie, where there are few connecting cards), on the river (when all community cards have been exposed) or as a continuation bet (ie, following up a pre-flop raise).
(Refresh your memory on how to read flops in the post-flop play section.)
On a dry board – If there are few to no draws possible – for example a flop of K♥7♦3♠ – then it is not possible to have a flush draw or an open-ended straight draw. Therefore it is not as important to protect a big hand because the chances of it being outdrawn are slim. Therefore it is OK to bet relatively little, in the hope of attracting a call to swell the pot. (Remember, if you typically bet small with a good hand then you should typically bluff small as well. Good opponents can spot changes in patterns and can figure out when you are bluffing and when you are not.)
On the river – If all the community cards are out already, no one can outdraw your hand. It follows that it is no longer necessary to protect a big hand. Therefore the situation is similar to an extremely dry board and bets on the river tend to be smaller than bets on other streets.
A continuation bet means to bet on the flop after raising pre-flop. You are continuing your aggression, hence the name. This is a way to pick up the pot if your opponent missed the flop. It’s not necessary to make a big bet in order to do so as your opponent should already be convinced of the strength of your hand from your pre-flop aggression.
In certain situations, big bets can be a very strong weapon. They will put a lot of pressure on your opponents and force them into decisions that can cost a lot of their chips. Big bets can be useful to bluff people off decent hands, gain huge value with strong hands or to protect against strong draws.
Here are typical situations when to make a big bet:
On a draw heavy board – In contrast to a “dry board” described above, you should bet big when there are many ways in which your strong hand can be outdrawn. Suppose you are holding 10♠5♥ in the big blind. Several players call and nobody raises, so you see a flop for free. It comes 10♣8♣5♦ and you have two pair.
You hand is strong at this stage, but a lot of cards are dangerous. Your opponents could easily make a flush, a straight or a better two pair on the turn or river. You should make a big bet here, possibly even bigger than the size of the pot.
Two pair is a hand that often calls for big bets because although it is strong enough to be ahead most of the time, it is weak enough that it can be outdrawn on turn and river. (This only holds true if there is no pair on the board. Otherwise a lot of players might have two pair and your hand is usually not strong enough to make a huge bet.)
Pre-flop – Before any community cards have been dealt, even a very strong hand can be vulnerable against a significantly weaker one. Even if you hold A♣K♥ and your opponent holds 6♦2♠ you are less than a two to one favorite. If you raise pre-flop it should almost certainly be a large raise to force out holdings that might beat you.
With the nuts – If you are lucky enough to have the best possible hand, you might want to bet big in order to build a gigantic pot. (Sometimes you also want to pretend to have the nuts and make a huge bluff.)
If you have decided that a bet is necessary, but the situation isn’t listed above, then a medium-sized bet is probably in order.
Bet Sizing Examples