Let us first start by explaining what "Mempool" is.
The mempool is where all the valid transactions wait to be confirmed by the Bitcoin network. A high mempool size indicates more network traffic which will result in longer average confirmation time and higher priority fees. The mempool size is a good metric to estimate how long the congestion will last whereas theMempool Transaction Countchart tells us how many transactions are causing the congestion.
In order to be confirmed, a transaction from the mempool needs to be included in a block. The size of a block cannot exceed 4 million weight units (1 million vbytes) , and each transaction has its own weight depending on the type of transaction, the UTXOs it spends (inputs) and the addresses it sends to (outputs)
Each Bitcoin node builds its own version of the mempool by connecting to the Bitcoin network. The mempool content is aggregated from a few instances of up to date Bitcoin nodes maintained by the Blockchain.com engineering team; this way, we gather as much information as possible to provide accurate mempool metrics.
Basically, the amount of transactions queued on the mempool dictates the amount of time that your transaction will take to be confirmed. During times of heavy traffic on the mempool (lots of transactions waiting to be confirmed) certain traders (buyers and sellers) pay higher fees in order to have their transactions confirmed sooner than other transactions with lower fees. When using a Bitcoin ATM, the amount of traffic on the mempool becomes very important, it dictates how long it will take for us to receive our bitcoins (or crypto being purchased at the BTM).
As a buyer, the Bitcoin ATM operator sets the fee that its paid for every transaction. Therefore this is impossible for the buyer to change. We suggest that if your transaction is urgent, you should check how busy the mempool is and/or contact the Bitcoin ATM operator to find out if their transactions are set to high priority, medium, or low priority. Rest assure that we choose the best settings for our clients transactions.
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