Coinflip
Heads or tails. Flip against the house, or challenge another player head to head.
Provably fair
Every Coinflip result comes from your own seed pair: a secret server seed (you see its hash first), your client seed and a counter. Sign in to see yours. Demo games use your browser's random numbers.
Recent duels
No duels settled yet.
Each duel's server seed is locked in (its hash is shown) when the duel is created. The joiner's browser adds a random seed when joining, so neither player can pick the result. Seeds are shown here once settled.
How Coinflip works
- Pick an amount and heads or tails.
- Against the house: flip instantly. A win pays 1.96×.
- Duel: your flip goes in the lobby. When another player takes the other side, the coin flips and the winner takes the pot minus a 3% fee.
Can I cancel a duel?
Yes, any time before someone joins — your stake comes straight back. Duels nobody joins are cancelled and refunded automatically after 60 minutes.
Who decides the result?
Nobody can. For duels, the result mixes a server seed committed before anyone joined with a random seed from the joiner's browser. For flips against the house, it comes from your own seed pair, just like Mines and Plinko.