If you’ve ever sent or received Bitcoin, you’ll notice that transactions aren’t quite instantaneous.
This is due to a feature of the Bitcoin blockchain known as block confirmations. Confirmations are an integral part of how the Bitcoin blockchain achieves such high levels of security.
Now that you have a background, this post will jump into:
Bitcoin confirmations are the network’s way of mathematically solidifying the idea that a given transaction has gone through. For every additional block confirmation that goes through, the network’s confidence that a given transaction is legitimate increases.
Exchanges like Coinbase require only 3 network confirmations, because at that point, mathematically speaking, its almost certain the transaction is correct.
Bitcoin and other blockchain networks collect transactions into “blocks.” These blocks are created on a schedule — on the Bitcoin network, for example, blocks are made roughly every ten minutes.
Faster blockchain networks such as Litecoin create blocks every 2.5 minutes. When you make a cryptocurrency transaction, a miner will scoop it up and add it to the next block.
Each block contains the transactions made on the cryptocurrency network, as well as a reference to the previous block added to the blockchain.
Confirmations are the number of times new blocks are committed to the blockchain after the block that contains your transaction.
Blockchain confirmations are important because as each successive block adds another strong guarantee of security that your transactions and the others included in your block are legitimate and immutable.
If a hacker targeting the Bitcoin network wanted to reverse transactions, they would need to decrypt the block that contains them.
If the block that contains the transaction they want to change is within a block committed to the blockchain several blocks ago, they’d also need to decrypt and alter every successive block — a virtually impossible task given the speed at which most blockchains commit blocks to the blockchain.
The number of transactions required to ensure a Bitcoin transaction varies depending on the purpose of the transaction.
Most cryptocurrency exchanges, wallets, and crypto payment platforms require three confirmations in order to approve a transaction. In most cases, this process takes 30 to 45 minutes.
The Classic Bitcoin client will list transactions with fewer than six transactions as “unconfirmed”, but three confirmations is the de facto standard for most cryptocurrency platforms.
These confirmations are used by exchanges and other cryptocurrency platforms to make sure the transaction is “safe” and has been successfully executed.
Larger transactions that hold a higher fiat currency value over $1 million USD typically require six confirmations or more in order to be considered complete.
Now that you have a background on confirmations and why they’re important, let’s jump into how to view them!
Depending on where you’re sending cryptocurrency, the receiving platform will typically provide information on how many confirmations a particular transaction has received.
Coinbase, for example, provides users with a simple link through to the Blockchain.com Block Explorer that provides confirmation information.
Block explorers are online blockchain browsers that can be used to view the number of confirmations for cryptocurrency transactions, as well as view wallet balances and transaction amounts.
Transactions made to Coinbase wallets can be viewed by clicking the transaction within the Coinbase wallet viewer, and clicking “view transaction” in the pop-up window:
Clicking this link will take you to the Blockchain.com Block Explorer, which provides information on the transaction size, date, amount, received time, fee, confirmations, and more.
Confirmation data is provided by the Blockchain.com Block Explorer in the left-hand column of transaction data.
If you’re using another cryptocurrency exchange or platform, it’s possible to view the total number of confirmations for a transaction by manually searching for the transaction ID on a block explorer. A transaction ID is a long, complicated number, and looks like this:
Block explorers can be used to manually search for this number and view the total number of confirmations. Blockchain.com’s Block Explorer allows users to paste a transaction ID in a search bar at the top of the Blockchain.com website:
Submitting your transaction ID to a block explorer will provide you with the total number of confirmations that have occurred for a transaction thus far.
Block generation on the Ethereum network moves much faster than the Bitcoin network, typically resulting in the commitment of new blocks to the Ethereum blockchain every 10 to 20 seconds.
Ethereum co-founder Vitalik Buterin has demonstrated that transactions made on the Ethereum blockchain can typically be considered as 99.99% secure after just 10 confirmations, which — depending on the number of pending transactions on the Ethereum network takes 3 to 10 minutes.
Most major cryptocurrency exchanges and trade platforms will require between 35 and 50 confirmations before considering an Ethereum transaction to be secure.
Etherscan is likely the most popular Ethereum blockchain explorer out there and contains functionality for tokens.
Major cryptocurrency exchanges will list incoming transactions as “pending” until a sufficient amount of block confirmations have been received, which can change depending on the cryptocurrency being sent or received.
Coinbase provides detailed information on the specific amount of confirmations required for each cryptocurrency the platform lists.
Bitcoin transactions sent to Coinbase wallets officially require 3 confirmations.
Coinbase Ethereum confirmation requirements are set at 35, while faster blockchains such as Litecoin require only 6 confirmations.
Binance has more relaxed confirmation requirements for transactions sent to Binance wallets. Bitcoin transactions that deposit BTC into Binance accounts require only 1 confirmation, while Bitcoin withdrawals require 2 confirmations.
Ethereum and other ERC-20 Ethereum Standard tokens need only 12 confirmations for both withdrawals and deposits.
It’s important to note that many cryptocurrency wallets allow users to set their own preferences for transaction fees. Transactions sent with lower fees are less likely to be added to blocks by miners, who want to complete higher-fee transactions first.
A transaction with a low fee is likely to take far longer to receive sufficient block confirmations to be considered “complete” by major cryptocurrency exchanges.
After reading this guide, we hope you understand:
We also recommend checking out this video on Bitcoin transactions:
Any questions about Bitcoin and cryptocurrency confirmations?
Let us know in the comments!