What Real Block Size Can be Expected After SegWit?


With the introduction of Segregated Witness (SegWit) in August 2017, the Bitcoin community witnessed a significant upgrade to the Bitcoin protocol. SegWit was designed to address certain limitations of the original Bitcoin blockchain, such as block size and transaction malleability. The implementation of SegWit brought about changes to the block size calculation, leading to a substantial increase in the effective block size. In this article, we will explore what real block size can be expected after SegWit and how it impacts the overall performance of the Bitcoin network.


Before SegWit, the block size limit for Bitcoin was set at 1 MB. This limitation posed a challenge as the number of transactions on the network increased, leading to congestion and higher transaction fees. The SegWit upgrade introduced a new way of storing transaction data by separating the signature data (witness data) from the transaction data, effectively reducing the size of each transaction. This change allowed more transactions to be included in a block without surpassing the 1 MB block size limit.


The actual block size after SegWit implementation depends on the mix of legacy transactions and SegWit transactions included in a block. Legacy transactions are those that do not use SegWit and still have their signature data attached to the transaction. On the other hand, SegWit transactions, also known as native SegWit or bech32 transactions, benefit from the separated witness data and are more space-efficient.


Initially, after the activation of SegWit, the increase in block size was not as significant as expected. This was due to the slow adoption of SegWit transactions, as many wallet providers and exchanges were still in the process of upgrading their systems to support SegWit. However, over time, the adoption rate increased steadily, resulting in a noticeable growth in the number of SegWit transactions included in each block.


As more and more transactions on the Bitcoin network transitioned to SegWit, the average block size started to rise. In some cases, the block size even surpassed 1 MB, allowing more transactions to be confirmed in a single block. This led to reduced transaction fees and faster confirmation times, benefiting users and businesses alike.


The effectiveness of SegWit in increasing the real block size can be illustrated by the concept of “block weight.” In the Bitcoin protocol, a block’s size is measured in bytes, but SegWit introduces the concept of block weight, which accounts for the traditional size of the block as well as the added weight of the segregated witness data. SegWit transactions have a lower weight compared to legacy transactions, making it possible to fit more transactions into a block.


Today, the adoption of SegWit continues to grow, and most reputable wallets and exchanges now support SegWit transactions. This widespread adoption has resulted in a more efficient use of block space and has significantly reduced transaction fees during periods of high network activity. With SegWit becoming the standard for Bitcoin transactions, users can expect to see larger real block sizes compared to the pre-SegWit era, leading to a smoother and more scalable network.


In conclusion, SegWit has been a game-changer for the Bitcoin network. By separating witness data from transactions, it has effectively increased the real block size, allowing more transactions to be processed in each block. As adoption continues to rise, the benefits of SegWit will become even more pronounced, ensuring a more robust and scalable Bitcoin network for the future. So, with SegWit leading the way, Bitcoin is better equipped to handle the growing demand for fast and cost-effective transactions in the digital age.