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All Cards on Deck! (JavaScript)

In this project, you will use JavaScript to model a deck of playing cards. You'll also add functionality to it such as shuffling and dealing.

Shuffling Cards

Computers are notoriously bad at random numbers. This is a pretty deep and complex topic, but it's worth pointing out that most random numbers we use in computing are actually "pseudorandom". For this assignment, you will read about, then implement, a popular algorithm that shuffles the order of a finite set using JavaScript's built in Math.random() function as a pseudorandom number generator.


  • Demonstrate usage of JavaScript objects and arrays to model resources
  • Understand and implement algorithms
  • Create an event-driven user interface


  • Your deck should contain 52 unique cards.
  • All cards should be represented as a string such as "Ace of Hearts"
  • There are four suits: "Clubs", "Diamonds", "Hearts", and "Spades".
  • There are 13 ranks: "Ace", "2", "3", "4", "5", "6", "7", "8", "9", "10", "Jack", "Queen", and "King".

You will model these in code, in any way you see fit. It may require you to experiment and try a number of techniques. There are many valid solutions. Your user interface should consist of a face down deck, and a face up "hand" of cards that have been dealt.

Read about, and implement the Fisher–Yates shuffle algorithm:

For our purposes, n is 52:

for i from n - 1 down to 1 do:
j = random integer (where 0 <= j <= i)
swap items[i] with items[j]


degit $GITHUB_USER/html-css-ts-project-template AllCardsOnDeckJS

Explorer Mode

  • The deck should be randomly shuffled when the page is loaded.
  • Clicking on the deck should deal a single card, making it visible in the face up hand.

Adventure Mode

  • Implement a way to deal cards into two or more hands

Epic Mode

  • Implement the game of War

Additional Resources

A Hint on Random Numbers

This snippet will give you a random integer, z between 0 and n:

const z = Math.floor(Math.random() * n)

Let's break this down from the inside out:

  1. For this example, assume n is 20.
  2. We use Math.random() to generate a floating-point number between 0 and 1. Let's assume our random value is 0.42.
  3. Multiply that number by n. If we think of this random value as a percentage, multiplying these gives us a number that is some "percentage" of n. Their product is 8.4, or 42% of n.
  4. We use Math.floor() to round down to the nearest whole number, i.e. 8.

Because we're rounding down, it's impossible to get 20. This will give us an integer between 0 and 19. This technique is perfect for finding a "random" index in an array of length n.

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