Skip to main content

What is a mempool

Mempool (memory pool) is a temporary storage area for unconfirmed transactions in a blockchain network.

Before being included in a block, transactions are first placed in the mempool.

Mempool explained simply​

A mempool is essentially a queue of transactions waiting to be confirmed and added to the blockchain.

How the mempool works​

When a user sends a transaction:

  1. the transaction is broadcast to the network
  2. it enters the mempool
  3. miners or validators select transactions
  4. transactions are included in a block

Why the mempool is important​

The mempool helps the network:

  • manage incoming transactions
  • prioritize transactions with higher fees

Example of a mempool​

During periods of high demand in the Bitcoin network, the mempool may contain thousands of pending transactions. Transactions offering higher fees are usually processed first.

FAQ​

What happens to transactions in the mempool?​

They wait until they are selected by miners or validators and included in a block.

Why can a transaction stay in the mempool for a long time?​

This can happen when the network is congested or when the transaction fee is too low.