In the world of blackjack, a little math goes a long way. Card counting, however much casinos try to prevent it, is a relatively easy way to up your chances of winning. It doesn’t take an MIT genius to figure it out, either. 

The premise of card counting in a game like blackjack is relatively simple, especially if there’s only one deck. If there is a high percentage of low cards that have already been played, chances are high that a high card like a king or a queen is going to show up. If you know that all four 10s in the deck have already shown up on the table, there’s no chance they’ll show up again. If there are two 10s on the table, you know there are two left in the deck. Get it? 

The Interactive Card Counting Trainer from the online casino 888casino will help you hone your card-counting skills. The training game helps you practice keeping a basic count based on what cards you see played in each hand. Every time you see a card lower than a seven, you add +1 to the count. Cards seven through nine are neutral, and high cards (tens, face cards, and aces) are -1. 

You can adjust the speed of the drills and choose between one and multiple decks. Because casinos don’t want to make winning any easier than it has to be, many blackjack tables use more than one deck, but you can still keep a count to have a rough idea of the probability of the card you want (or really don’t want) showing up on your next hit. 

Play here. But just remember, while card counting gives you a slightly better idea of what’s coming up in the deck, it’s not a magic trick, and luck can still turn against you.   

For more on the world of mathematical card game theories, read our guide to card counting, or check out what happened when our writer hit up Atlantic City with the help of an MIT poker course. 

[h/t Gizmodo]