Transaction fees are included with your Bitcoin transaction to ensure it is processed by a miner and confirmed by the Bitcoin network. The space available for transactions in each block is currently limited to 4 million weight units, which corresponds to approximately 1.3 to 2 MB of actual transaction data, depending on the structure of the transactions, such as SegWit or legacy types. This means that to have your transaction confirmed quickly, you may need to outbid other users.
What does sats/vB mean and how is the fee calculated?
The transaction fee is always displayed in Sats/vB. This means Satoshis per virtual byte.
This means Satoshis per virtual byte, where 1 vB (virtual byte) corresponds to a unit of transaction weight (1 vB = 4 weight units).
So if a transaction has e.g. 250 virtual bytes, the following is calculated with a fee of 50 Sats/vB:
50 × 250 = 12,500 satoshis (0.00012500 BTC)
You can see how large a transaction is on average and how busy the network is at mempool.
Why is the Bitcoin network fee so high?
Transaction fees are directly related to the demand on the Bitcoin network. A block always has the same size and therefore cannot hold more transactions than intended. Accordingly, the fee is adjusted to the demand, as in an auction. If the fee is very high, wait a while until the demand decreases and then place your transaction.
