The object of 21 is to score 21 points in as few turns as possible.

To begin the game, you must select a card by clicking the top of the card stack. The card will reveal a category and the option to play for up to 11 points.

The higher the points, the more difficult the question will be. Lower point value questions will be true or false format while higher point questions will have as many as four choices.

Answer the question correctly to earn points. If you choose a wrong answer, you will get a strike. Three strikes and the round is over.

Each point has a value of $10 and you can earn a bonus depending on how many turns it took you to reach the target 21. The final BONUS round is worth $10,000 per point.

The bonus round includes up to six true or false statement. The first question is worth one point, the second is worth two points and so on. The sum of all six questions equal 21, and worth a total of $210,000. You can decide to play on or stop after each correct answer. Choosing to continue risks the money you have earned in the bonus round. Choosing to stop will keep the money you have earned in the bonus round and add it to your total score.