One hash at a time

Click to run a local proof-of-work. We use the current time in milliseconds as the base (later: a real block template) so each run has a different base and nonce. We search for a nonce so the SHA-256 hash starts with "00" (first byte zero). Usually takes hundreds of attempts. All in your browser.

Target: hash starts with "00". Base = time (ms) at click; next run will use a new base.

This is a demo proof-of-work in the browser. The base is currently a timestamp (ms); it will be replaced by a real Bitcoin block template. For illustration only.