What Is the Difference between Block Size and Block Weight in Bitcoin?

Block size traditionally referred to the hard limit of 1 megabyte (MB) for a Bitcoin block. Block weight is a newer concept introduced with the Segregated Witness (SegWit) upgrade.

Weight is a measure that assigns different values to different parts of a transaction's data. Specifically, witness data (signatures) is weighted less heavily than other transaction data.

The block weight limit is 4 million units. This change effectively allows blocks to be larger than 1MB in data size while maintaining the spirit of the original limit, thus increasing network capacity.

What Is the Difference between a TWAP and a Volume-Weighted Average Price (VWAP)?
How Does the Block Size Limit Create Scarcity for Block Space?
What Is the Relationship between the Block Size Debate and Transaction Fees?
How Does the Block Limit Influence the Maximum Number of Transactions per Block?
How Does the ‘SegWit’ Upgrade Affect the Calculation of Block Space?
How Do Segregated Witness (SegWit) Upgrades Aim to Address Block Space Constraints?
What Is the Primary Difference between TWAP and Volume-Weighted Average Price (VWAP)?
What Is the Difference between a “Time-Weighted Average Price” (TWAP) and a “Volume-Weighted Average Price” (VWAP) in a Fixing Process?

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