Human vs machine
Rock paper scissors, against an AI that learns you.
Every throw teaches it your habits. It predicts your next move, and shows you the read. Think you can stay random?
Pick a hand to start. The AI starts out guessing, then it starts reading.
AI pattern lock
0%
Ten models watch your throws, from favourite-hand bias to Markov chains to a sequence matcher. Each one is expanded into three levels of second-guessing, and the levels that have actually been winning get the weight.
Not your average rock paper scissors game
Most online rock paper scissors games pick a hand at random. This one does not. It builds a model of how you throw, tells you what it has spotted, and adjusts every single round.
It never cheats. Each round the AI commits to its hand using only your past moves, so it cannot see the hand you are about to play. It wins by prediction, and when it has nothing to go on it plays an even mix instead of forcing a guess.
Play twenty rounds and the read panel will start naming habits you did not know you had. Most people cannot stay random for long, which is exactly what makes the game interesting.
How to play
- 1
Pick a hand
Click rock, paper or scissors, or press R, P, S (or 1, 2, 3) on your keyboard.
- 2
Watch the read
After each round the AI names the habit it thinks it has spotted, and whether it paid off.
- 3
Try to stay random
The pattern lock bar shows how strongly it has you. Drive it to zero and you have genuinely shaken it off.
Where the name comes from
The English name is simply a list of the three hands, but the game reached the West from Japan, where it is called janken. Older English sources sometimes call it roshambo, a name still common on the American west coast and of disputed origin.
The counting chant in English is "rock, paper, scissors, shoot", with the throw on the final word. In Britain the shorter "rock, paper, scissors" is more usual, with the throw on "scissors", which is a reliable way to start an argument between two players from different countries.
Rock Paper Scissors · roshambo · rock scissors paper
Frequently asked questions
How does the AI predict my moves?
Ten lightweight models watch your throw history: your favourite-hand bias, Markov chains over your last one, two and three hands, what you throw in response to the AI's hand, how you react to winning and losing, and a matcher that hunts for the longest run of play it has seen before. Each model is then asked how many moves ahead you are thinking, giving 28 candidate strategies, and the ones whose moves have actually been winning get the weight.
Can I beat the AI?
Yes, by being genuinely unpredictable. Rock paper scissors has no winning strategy against true randomness, so a perfectly random player holds the AI to about a third of all rounds, which is a straight coin flip once draws are set aside. The catch: humans are famously bad at being random, and trying to outguess the AI is itself a pattern it is built to catch.
Is this rock paper scissors game free?
Completely free, no signup, no downloads. It runs in your browser on desktop and mobile. Your moves are analysed on your own device and stored only in your browser, so the AI remembers you between visits without anything leaving the page. Only anonymous win, loss and draw tallies are counted for the global scoreboard.
What beats rock in rock paper scissors?
Paper beats rock. Rock beats scissors, and scissors beats paper. The three hands form a perfect cycle where every throw beats one hand and loses to the other.
How do I play rock paper scissors online with the keyboard?
Click a hand or use the keys R, P and S (or 1, 2, 3) to throw rock, paper or scissors. The AI commits its move before your pick is revealed to it, every round, so it wins by prediction and never by peeking.