The Bitcoin scalability problem refers to the limited capability of the Bitcoin network to handle large amounts of transaction data on its platform in a short span of time.[1] It is related to the fact that records (known as blocks) in the Bitcoin blockchain are limited in size and frequency.[2]
Bitcoin's blocks contain the transactions on the bitcoin network.[3]: ch. 2 The on-chain transaction processing capacity of the bitcoin network is limited by the average block creation time of 10 minutes and the original block size limit of 1 megabyte. These jointly constrain the network's throughput. The transaction processing capacity maximum estimated using an average or median transaction size is between 3.3 and 7 transactions per second.[2] There are various proposed and activated solutions to address this issue.
The maximum throughput is the maximum rate at which the blockchain can confirm transactions. Today, bitcoin's maximum throughput is 3.3–7 transactions/sec [1]. This number is constrained by the maximum block size and the inter-block time.