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Please click DONE when you are bored, don't just browse away or close window! See WHY, hint: for science! Press "a" to add all, and "s" to multiply all, and "esc" to cancel one move.

Basic Rules of the game

Your goal is to use all 4 given numbers and basic arithmetics (+ - × and /) to get 24 as fast as you can. More information. To play the math 24 game on this site or on the apps we built, you don't ever need parenthesis. If you found a solution for (a,b,c,d) as a × (b - c) + d, you simply click b,-,c,×,a,+,d in that order. Our game will combine the intermediate result into one number and you never need to input a parenthesis.
We have several types of games for you.

Solo game:

Beat the clock: You start with 120 seconds, solving a puzzle you gain 10 seconds on the clock, while skipping a puzzle you lose 20 seconds. Your final score will be your in-game score plus time left on the clock.
No time limit: In this game, players never die. Your final score will be your in game score plus bonus.
bonus = max (30 × num_solved - 10 × num_skipped - time_used, 0)

Multi-player games:

Live!: This is one of our most popular games. Play with other players around the world. We give out a new puzzle every minute and rank players instantaneously.
Battle mode!: You solve 5, 10 or 20 puzzles and send a challenge to your friends. You will get a report on who wins after they finish the challenge.

Hot Keys

Use both mouse and keyboard can greatly improve your time.
The most useful two keys are A and S. At any time, press A to add all the numbers left in the game, and press S to multiply all the numbers left in the game. For example, if you have 8 8 8 left, the solution is obviously 8 + 8 + 8, you only need to hit A on your keyboard. This is much faster than clicking 5 times with your mouse. Other keys are shown in the figure below. If you use a traditional keyboard and has numpads, you can also use 4 for the upper left number, 5 for the upper right, 1 for the lower left and 2 for the lower right.
The goal of the implementing hot keys is to reduce the play time, we want to measure your reaction time not how fast you can click. So let me know if you have any suggestions on more hot keys.

More

After solving or skipping a puzzle, you can view all the unique solutions for T seconds (T = 4 + number_of_unique_solutions). By clicking "Never show solutions again", you will not have the T-seconds break anymore between puzzles.
After solving each 100 puzzles, you can have a 10 minute coffee break (of course you can resume play anytime during the break).
In-game score: you will soon notice that not all puzzles have the same in-game score. The score of a puzzle = 10 × ( 1 + 2 / number_of_unique_solutions).