The probability is exactly one half: the outcome is the lowest bit of
H, the keccak256 hash of the house signature over your bet, and that bit cannot be steered by you or the house.
How a round plays
- Choose heads or tails and your stake.
- Confirm the transaction. Your pick, stake, and address are hashed into a digest the moment it lands.
- The house signs the digest. The coin animation replays what the signature already decided.
- A win pays 1.9x to your wallet, automatically within seconds, or instantly if you press Collect.