In poker, the more outs you have the better. Outs are the cards that you need to come out on the board to complete or improve your hand.
The more outs you have, the higher the percentage you have in getting the cards you need. There are odd charts to show the exact percent chance
of catching your card on the turn and river. We are not going to worry about this because it is hard to memorize all of these numbers. There is a quick calculation you can do in your head that is pretty accurate.

To figure your number of outs you have to think about what is possibly left in the deck. For example if you have Q-10 in your hand and the flop is 6-3-J. Then if you catch a Q you should be ahead. There are 3 Q’s
possibly left in the deck giving you 3 outs. If a 9 comes out on the turn then you can wait for your Q for the highest pair on the board, a K, or 8 for your open ended straight draw. You have 3 Q’s, 4 K’s, and 4 8’s giving you 12 outs for the turn.
Make sure you are aware of all your outs from pairs, straight draws, flush draws (there are 13 suited cards), and straight flush draws.

Once you have figured out your number of outs, you can multiply this number by 4. This number gives you the percent chance of catching one of your needed cards on the turn or the river.
If the river card is the only card you are waiting for, you multiply your number of outs by 2.

If we look at the above situation, after the flop, our 3 outs give us about a 12% chance of catching. After the turn we now have 12 outs giving us a 24% chance of catching.

Lets say we have Kh-Jh and the flop is 10h-Qc-7h. You have 3 outs from your K’s, 9 outs for your flush, and 6 outs from A’s or 9’s for the straight, it is not 4 for each because two are hearts. That gives 18 outs and about a wopping 72% chance to catch on the turn or river. After the river you have about a 36% chance.
But please note that When you are dealing with more than 10 outs, the actual percentage will drop a little with each out. See the odds chart.

You may also use an easy to use tool to calculate your odds by CLICKING HERE