Block height is a block's position in the chain, counting from 0 at the genesis block. Learn how heights schedule halvings, timelocks and confirmations.
Counting from zero
Height is simply how many blocks come before a block. The The genesis block is height 0, the next is height 1, and so on.
Why heights are useful
- A simple clock. Bitcoin uses heights to schedule events: the halving happens every 210,000 blocks, Difficulty adjustment every 2,016.
- Timelocks. A locktime below 500,000,000 is a block height.
- Confirmations. Confirmations = current tip height − block height + 1.
Height isn't unique, a hash is
For a short time two blocks can share the same height (a fork). The block hash is the true unique ID; height is a convenient position.
Famous heights
| Height | What happened |
|---|---|
| 0 | Genesis block |
| 170 | First person-to-person transaction |
| 210,000 | First halving |
| 481,824 | SegWit activated |
| 709,632 | Taproot activated |
| 840,000 | Fourth halving |
Look up any height
Type a number into MyBitcoinExplorer's search to open that block: for example 840,000, the 2024 halving, or 0, the genesis block.
Height and time
At about 144 blocks per day, you can estimate when a future height arrives: 52,560 blocks is roughly one year. Because block times vary, such estimates can drift by days.
Key takeaways
- Height is a block's position in the chain, starting at 0.
- Bitcoin schedules halvings and difficulty changes by height.
- The hash, not the height, uniquely identifies a block.
Common questions
What is the current block height?
It grows by about 144 per day. Our status page shows the height our node has verified.
Is block height stored in the block?
Not in the header, but since BIP 34 it must be written at the start of the coinbase transaction.
What is the current Bitcoin block height?
It grows by about 144 blocks a day. Our homepage and status page show the latest height our node has verified.
What is the difference between height and depth?
Height counts from the genesis block; depth (confirmations) counts back from the latest block.