Best of 1, 3, 5 or 7 with a fair random computer and an optional predictor that learns your habits.
Rock paper scissors is a hand game for two players in which both choose rock, paper or scissors at the same moment: rock beats scissors, scissors beat paper, paper beats rock, and the same choice twice is a draw. On this page you play the computer. Tap a move, or press 1, 2 or 3, and the computer shows its choice after a short shake. A drawn round does not count toward the match and is simply played again. A match is a best of 1, 3, 5 or 7 series: the first player to win 1, 2, 3 or 4 rounds takes it. The score, the list of rounds and your record of matches won are shown on the page.
By default yes. The computer picks each move at random with equal chance for every move, using your browser's secure random number source (the same one used for passwords) when it is available, so it does not look at your earlier moves and has no pattern to find. Against a fair opponent no strategy wins more than one round in three in the long run. If you want a challenge, switch the computer to predictor in the menu. The predictor is clearly labelled on the page. After you have played three moves it guesses your next move from how often you play each move and from what you played after your previous move, then plays a move that beats its guess. If you repeat yourself or cycle through the moves it will start to win. If you play at random it cannot do better than chance.
A single round is a coin flip with a possible draw, so a series gives a fairer result. In a best of 3 the first to 2 round wins takes the match, in a best of 5 the first to 3, and in a best of 7 the first to 4. Against a fair random computer your chance of winning a round is the same whichever you pick, 1 in 3, but the longer series smooths out luck: you win a best of 1 against the fair computer about half the time, since draws are replayed. Draws are not counted toward the series, they are shown in the score and the round list. Pick best of 1 for a quick decision, such as who goes first, and best of 5 or 7 when you want a result that is harder to win by one lucky streak.
On a computer, press 1 for rock, 2 for paper and 3 for scissors. The tap targets are large for phones. Your best-of choice and computer type are saved in this browser, and so is your record of matches won, kept separately for each match length and computer type so a win in a best of 1 or against the fair computer is not mixed with one in a best of 7 or against the predictor. The record counts finished matches, not single rounds. If your browser blocks storage the page says so and nothing is kept. Nothing about your moves is sent anywhere. The page counts visits with Google Analytics and never your moves.
Rock beats scissors, scissors beat paper and paper beats rock. If both players choose the same move it is a draw and the round is played again. In this game a drawn round does not count toward a best of 3, 5 or 7 match.
Three. Best of 1 needs 1 round win, best of 3 needs 2, best of 5 needs 3 and best of 7 needs 4. Draws are replayed, so a best of 5 can take more than 5 rounds in total.
By default it is random, with a one in three chance of each move, and it ignores what you played before. The predictor option is different and is labelled: it learns your habits after 3 moves and tries to beat your likely next move.
It counts how often you play each move and what you played after your last move before. Each repeat of that pattern counts double. It then picks a move that beats its guess. Someone who plays rock three times in a row will be answered with paper.
Not in the long run. With equal random choices each round is a win, a loss or a draw with probability 1 in 3 each, so about 33 of every 100 rounds are wins whatever you play. Streaks happen by chance, for example 5 wins in a row.
Each setup has its own record: best of 1, 3, 5 and 7, each with the fair computer or the predictor, so 8 separate records in total. Switching from best of 1 to best of 7 shows the best of 7 record, which starts at 0 of 0.