INTERACTIVE LAB · NO REAL FUNDS

Why is a changed record detectable?

Edit a middle block and compare original fingerprints with recomputed links.

Preparing the experiment…

Why does this happen?

Editing data invalidates its original fingerprint. Recomputing it changes later references too. Real Bitcoin also uses proof of work to make rewriting history costly.

Keep learning

Why can’t bitcoin be spent twice?What do Bitcoin confirmations mean?

Primary evidence

Bitcoin Developer Guide