Block Height

What is Block Height?

Block height is the sequential number of a block in a blockchain. It represents the position of a specific block in the timeline of the network, starting from zero.

How does Block Height work?

1. The very first block (the Genesis Block) is assigned a height of 0.
2. Every subsequent block added to the chain increases the height by 1.
3. The "current block height" is the total number of blocks minus one.
4. Block height is used to measure the "age" and progress of the chain.
5. Nodes use block height to determine which version of the chain is the longest and most valid.

Why does Block Height matter?

It provides a universal timestamp-like reference for all network participants. Developers use block height to schedule protocol upgrades (hard forks) and dApps use it to trigger specific events at a precise time.

Key features of Block Height

• Numerical sequence (0, 1, 2, ...)
• Constant increment for every new block
• Determines the "length" of the blockchain
• Used for scheduling network upgrades
• Provides a way to reference a specific point in history

Examples of Block Height

• Bitcoin reached a block height of 840,000 in April 2024.
• A project announcing a "snapshot" for an airdrop will occur at block height 15,000,000.
• Ethereum's "Merge" upgrade was triggered at a specific Terminal Total Difficulty, not just a height.