Sepolia · Record

4 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 · 56 min ago
Expires
Oct 16, 2036
Commitments
0

The instance

Derived from the hash of block 11,947,845. Anyone can recompute every value below from the spec and the chain.

Level id
0x15f2e7eabc0b3c00c2e47ecc9cd3b44fb389aacf8618f6252fe7185721d77ad9
Seed
0x0a94f5ddec48ccf1afd61b28be17d60b83ab2b0ef8986fd88615175b08d16ea0
Function
Keccak[r=1440, c=160], 4 rounds, 80-bit output
Target bits t
80
Target T
0x57ad9bc858b5f7bc8b4f
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.