How To Memorize A Card In A Deck

Despite the lack of sleep (I’ve been up for almost 24 hours), I’ve devised a fairly simple way to memorize a single card within a deck. It comes in the form a little trick you can play on friends into fooling them that you can count cards like Rain Man. It actually works with simple addition so most people should be able to do it with a little practise.

By applying a unique value to each rank (Ace, 2, 3, 4, 5, and so on), you can determine the total value of the entire deck:

Card Value
Ace 1
2 2
3 3
4 4
5 5
6 6
7 7
8 8
9 9
10 10
Jack 11
Queen 12
King 13

Using the sum of 1 through to 13, the value of each suit is 91, and therefore the entire deck's value is 364.

Knowing that the entire deck equates to 364, by removing any one card, the deck’s value will lower by the value of that card. For example, if an Ace (1) is removed, the deck’s value will fall to 363.

So by getting a friend to remove a card, you can determine their card by simply adding the remaining cards. It takes a few minutes and will only tell you the rank of the card, not the suit, so it’s probably best to run through the deck again and take out the remaining three cards of that rank to “prove” you know what card they had. This trick works a treat but you can very easily mess up your count, so be sure to take your time otherwise you may end up with the wrong card.

If that’s too easy, you can always make things a little more difficult by applying a unique value based on the bumps/points its suit has:

Suit Points/Bumps
Spades 1
Hearts 2
Clubs 3
Diamonds 4

In practise:

Card Value
Ace of Spades 1
Ace of Hearts 2
Ace of Clubs 3
Ace of Diamonds 4
2 of Spades 5
2 of Hearts 6
2 of Clubs 7
2 of Diamonds 8

Note that with this system, the deck’s value will be 1378, as proven below:
Using the sum of 1 through to 52, the value is 1378.

A simple method to memorize each card might be to minus 1 from the rank, multiply by 4, then add the bumps/points (for example: 4 of Diamonds is 3 multiplied by 4, add 4; this equals 16).

With both systems, it might be wise that whilst counting, to reset every time you hit 100 (for example: with a count of 96, a 6 would cause the running count to fall to 2 instead of 102). This way, keeping count should be a lot easier. Good luck.