Proof of Work
Mine a hash with leading zeros — experience Bitcoin-style proof of work right in your browser.
Mining Configuration
1 (trivial)4 (moderate)7 (hard)
How Proof of Work Works
Proof of Work (PoW) is a cryptographic puzzle system that requires a prover to expend computational effort to produce a result meeting certain criteria. The most common form — used by Bitcoin — requires finding a nonce (a random salt) such that when combined with input data and hashed, the resulting hash begins with a certain number of zero bits (or hex characters).
The difficulty scales exponentially: each additional leading zero approximately doubles the expected search time. With 4 leading zeros, you need to try ~65,536 nonces on average. With 8 zeros (~16 hex chars), the expected attempts exceed 4 billion.
1 leading zero
~16 attempts
2 leading zeros
~256 attempts
4 leading zeros
~65K attempts
6 leading zeros
~16M attempts
ℹ️ This simulator uses SHA-256 with a random nonce appended to your input — exactly like Bitcoin block mining. Everything runs in your browser via the WebCrypto API.