02 / Coin Flip Challenge
FLIP THE
TRUST
Your opponent is a simulated rival in this page. Can you create a fair coin toss without trusting their word? Inspect their seal, outsmart leaks, and catch fake reveals.
You don't get points for guessing a random coin flip. You earn them by verifying real commitments and spotting how protocols can fail.
SECURE CONNECTION STARTING
Both players choose one secret bit.
The opponent posts a hash commitment before your choice. You commit your own bit, then combine both bits with XOR after verification.
Opponent's published SHA-256 seal:
Establishing…Recomputed seal from disclosed bit + nonce:
Reveal requiredDetect a weak seal
Your rival accidentally published the nonce early! Only two secret bits are possible. Hash each candidate to learn what they hid BEFORE you choose yours.
Try both candidates. The matching fingerprint exposes the secret bit.
Choose your private bit
0 XOR 0 = Heads, 1 XOR 1 = Heads. Different bits produce Tails. A valid result requires both genuine openings.
Time to reveal
Your verdict
What does the evidence actually prove? The correct answer earns two trust points. Each mission can be retried in another run.
Round result
Your six-case audit
Creating the opponent's commitment…
Where this leads
From coin flips to commitments
A valid hash can be leaky, a dishonest opening can fail verification, and a player can still abort. Commit Gate examines hiding and binding beyond a two-choice game.
Safety boundary: Demonstration only. The opponent, cheating scenarios and client-side reveals are simulated locally. Real SHA-256 and cryptographically random nonces power the receipts. No betting, accounts, network requests or analytics.