Dive into the mempool: insights and tips for Bitcoin transactions

The mempool is a crucial part of the Bitcoin network. It acts as a sort of waiting room for all unconfirmed transactions before they are added to the blockchain. In this blog post, we would like to explain what the mempool is and how it connects to the fees for Bitcoin transactions. Last but not least, we have a tip on how you can save transaction fees by briefly analyzing the mempool.

What is the mempool?

The mempool is a crucial part of the Bitcoin network that is often overlooked. It acts as a sort of waiting room for all unconfirmed transactions before they are added to the blockchain. Every time a Bitcoin user wants to make a payment on-chain, this payment is propagated as a transaction throughout the network. These transactions accumulate in the mempool until they are included in a new block by the miners.

The size of the mempool and the associated transaction fees fluctuate constantly. This is because the network can only process a limited amount of transaction data per block, which leads to competition for the limited space in the next block.

How deep is the mempool?

The volume of the mempool, i.e. the number of people waiting in the waiting room, is influenced by a variety of factors, including the trading behavior of users and global activity on the network. For example, large fluctuations in the Bitcoin exchange rate often cause an increase in transactions, as many users want to react quickly. If the rate of transactions created exceeds the supply of available block space, the mempool grows faster than transactions can be confirmed.

Interestingly, transaction creation appears to follow daily and weekly patterns, with activity increasing at the start of the business day in Europe and decreasing again after close of business on the US West Coast. In general, transaction volume decreases over the weekend, leading to a reduction in mempool volume.

Reading and understanding mempool charts

The mempool can be viewed via various online services such as the well-known mempool.space service. These show data for an individual node and provide a visual representation of the mempool size in megabytes as well as the outstanding transaction fees.

The colored bands in the chart represent different fee ranges. Different colors are usually chosen for the different services. In all cases, however, the color bands show a transition from transactions with low urgency to transactions with medium priority to transactions that require quick confirmation.

Source: Screenshot from the weekly view of mempool.space on 09.11.2023

The right time for your transaction

The decision of when to send a Bitcoin transaction should be based on the urgency of the payment. If you need a quick confirmation, e.g. for a payment that is urgently expected by the recipient, you will have to pay a correspondingly higher fee. However, if you are flexible, you can wait until the size of the mempool decreases and get away with a lower fee. Sending transactions at the weekend can be an effective strategy, as activity on the network is generally lower.


Analyzing the mempool can help you optimize fees for Bitcoin transactions. By understanding the patterns of mempool activity and adjusting transaction fees accordingly, you can save costs and make your transactions more efficient.

At Coinfinity, we send your Bitcoin in a collective transaction together with other buyers wherever possible to keep the transaction costs low for you. Try it out now, for example with a savings plan.

The Coinfinity Bitcoin App is here! Stay humble, stack sats.