# Genesis Block

> The very first block of a blockchain.

Canonical URL: https://fudfomo.co/glossary/genesis-block
Source: What The Block! Dictionary v1.0 (last updated 2026-04-25), browsable at https://wtb.fudfomo.co.

## Definition

The genesis block is the first block in any blockchain and the only one not built on top of a previous block. Bitcoin's genesis block was mined in January 2009 and famously contains a newspaper headline in its data.

Networks often hard-code the genesis block into their software, so every node starts from exactly the same point.

## Related terms

- [Block](https://fudfomo.co/glossary/block): A bundle of transactions added to a blockchain together.
- [Block Height](https://fudfomo.co/glossary/block-height): The number of blocks that have been added to a blockchain since its very first one.
- [Bitcoin](https://fudfomo.co/glossary/bitcoin): The first cryptocurrency. A digital money you can send anywhere in the world without a bank, secured by a network of computers.

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