TwirlseedFlip a coin
Heads or tails, chosen fairly before the coin moves.
Recent flips
How it stays fair
Every result comes from your browser’s cryptographic random source. Rejected draws remove rounding bias. The answer is chosen before the animation starts.
A real coin is not quite fair. In 350,757 hand flips, coins landed the same way up they started 50.8% of the time (Bartoš and colleagues, 2023). This one is exactly 50/50.
Twirlseed gives heads and tails an equal chance with your browser’s cryptographic random source.