Sepolia · Frontier

6 rounds reduced rounds

Find a preimage for round-reduced Keccak, the shape of the Crunchy Contest.

Open
Prize
Record level, no prize
Estimated cost
From published attacks
Opened
Oct 19, 2026 · 3 h ago
Expires
Oct 18, 2028
Commitments
0

The instance

Derived from the hash of block 11,947,420. Anyone can recompute every value below from the spec and the chain.

Level id
0x7912cc18c43ab49bf013237adcae0e0a8c69d1835b19123360fc88fd2c3025dc
Seed
0x45cea03acc47db0cdf3cc37d13623eda23704c25ca66f90c47d9d8f7d4952ed3
Function
Keccak[r=1440, c=160], 6 rounds, 80-bit output
Target bits t
80
Target T
0x11235a47195d7c935cba
Contract
0x5D6322…C48277

Claim

Solved it? Check the answer here, then commit and reveal. The reference solver and the spec are in the method notes. How to solve

  1. 1

    Connect a wallet

    No browser wallet found. Any EIP-1193 wallet works, on Sepolia.

  2. 2

    Check your solution

    Checked in your browser against the live instance. Nothing is sent until you commit.

  3. 3

    Commit

    Publishes a fingerprint of your solution bound to your payout address. Nobody can read the solution from it, and copying it would still pay you.

  4. 4

    Reveal, then get paid

    Reveal once your commitment is 3 blocks old. The earliest commitment with a valid reveal is paid after a …-minute settlement window.

Your salt is kept in this browser and in the receipt file. Without it a commitment cannot be revealed. Every claim from this browser is listed under My claims.

History

Every event for this level, from the contract.