Sats/vB is the fee rate a user is willing to pay for a miner to validate their Bitcoin transaction.
What Is Sats/vB?
Before the Segwit upgrade, the Bitcoin fee rate was measured in satoshis per byte. However, after the Segwit fork, it is expressed in satoshis per virtual byte, short for “sats/vB” or “sats/vByte.”
Therefore, sats/vB refers to the fee rate you are willing to pay for a transaction to be confirmed in the Bitcoin blockchain.
Sat/vB typically measures the priority of an unconfirmed or pending Bitcoin transaction in a node’s mempool. Put another way, selecting a higher sat/vB when sending BTC typically results in faster transaction confirmation times. The fee rates are typically displayed on blockchain explorers, such as mempool.space.
Simply put, the total fee a user pays for a Bitcoin transaction is the product of the transaction size (in virtual bytes) and this fee rate (sats/vB). For example, if a transaction has 1000 virtual bytes and a fee rate of 40 Sats/vB, the actual transaction fee is 1000 * 40 = 40,000 Sats. This is equivalent to 0.0004000 BTC.
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