You sent some BTC from your wallet, but it didn’t go through. You waited a while, but the person you sent it to didn’t receive anything. How come? And how can you be sure that all the funds you send will reach their intended destination?
Understanding blockchain transaction speeds
Blockchain transactions can be slow due to various factors:
- Network Congestion: High traffic on the network can delay transaction processing.
- Block Size and Time: The size of each block and the time it takes to mine a new block affect transaction speed.
- Transaction Fees: Higher fees can incentivize miners to prioritize certain transactions.
- Consensus Mechanism: Different consensus mechanisms (Proof of Work, Proof of Stake, etc.) have varying processing times.
How transaction fees affect blockchain transactions
It’s important to remember how transactions are processed. First, the transaction is sent to all miner nodes and placed in a queue for processing, known as a memory pool (mempool). Miners consolidate several thousands of transactions into a draft block for the blockchain and try to ‘mine’ it. When one of them is successful, the transaction is entered into the block and the miner receives a commission for processing it.
The commission is the key here. If the sender wanted to save money and set a small reward, the transaction would have a lower processing priority. However, the commission size isn’t fixed and depends on network congestion.
Methods to speed up blockchain transactions
If you need to send cryptocurrency as quickly as possible, choose the current ‘ballpark’ reward amount or higher. You can find out the current levels using specialist services. Our mobile app calculates the fee automatically, and you can set the priority level to Slow, Market, or Fast.
You can also set a custom transaction fee to override the recommended commission.
So what happens when you’ve set a low commission, the network is experiencing high loads, and your crypto assets get ‘stuck’?
If you decide to play the waiting game, there are two options:
- Your transaction will be processed, but there is no way of knowing how long it will take
- Your transaction will be ‘evicted’ from the mempool (usually takes around 48 hours), and the cryptocurrency can be used again.
Replace-By-Fee (RBF) feature
This is a feature in the Bitcoin network that allows a sender to replace their unconfirmed transaction with a different version of that transaction that has a higher transaction fee. RBF allows senders to raise the fee to confirm their transaction faster.
Since all the parameters (inputs and outputs) remain unchanged, the nodes will perceive it as identical to the old transaction, but the larger commission means it will receive a higher priority in the mempool. However, not all wallets support RBF.
Child-Pays-For-Parent (CPFP
Another method is Child-Pays-For-Parent (CPFP). This involves creating a child transaction with a higher commission. The trick lies in the fact that the new transaction must be sent to the ‘change address’ of the one that’s stuck (in essence, we are sending the cryptocurrency to ourselves, but ‘tying’ the transaction to the previous one).
The reward amount should be set at a level that covers both transactions and is high enough to be attractive to miners. Since the child transaction cannot be confirmed without the parent transaction being confirmed, both will be processed.
Transaction accelerators
You can also use transaction accelerators. Transaction accelerators are services designed to help users speed up blockchain transactions, especially when they are delayed due to network congestion or low transaction fees.
All you need to do is feed them the TXID of the transaction that’s become stuck, and everything else rests with the accelerator.
Some simply relay the transaction across the network nodes, reminding the miners of its existence and returning it to the memory pool. Others are mining pools (or use partner pools) that, for a fee, insert the stuck transaction into the next block to be mined.
How transaction accelerators work
Transaction accelerators prioritize transactions for inclusion in the next available block. They do this by incentivizing miners to process these transactions, usually through additional fees or by leveraging partnerships with mining pools.
Types of transaction accelerators
- Paid accelerators
Paid accelerator services charge a fee to expedite transactions. They work by paying miners extra to prioritize your transaction. Typically, they're more reliable due to the direct financial incentive provided to miners. Free accelerators
Some mining pools offer free acceleration services, but availability and reliability vary. Users submit their transaction IDs to the accelerator, which prioritizes these transactions.
Popular Transaction Accelerators
- BTC.com Transaction Accelerator
This is one of the most well-known accelerators for Bitcoin transactions. Users submit their unconfirmed transaction ID (TXID) to the BTC.com Transaction Accelerator. However, the free service has limited capacity and may not guarantee acceleration, whereas the paid service provides higher priority. Transactions are prioritized for inclusion in the next block mined by BTC.com's associated mining pool.
- ViaBTC Transaction Accelerator
ViaBTC is one of the oldest and most popular mining pools. Its Transaction Accelerator service has both free and paid versions. The free version is limited to 100 transactions per hour for everybody. When the network load is particularly high, it can be difficult to join this group of 100.
Since the counter is reset every hour, it might make sense to start trying to add the transaction’s TXID during the last few seconds of the hour. However, this approach isn’t guaranteed to work and might require a few attempts. Another drawback of the free version is that it uses ViaBTC’s own computing power, while the paid acceleration service uses additional partner pools.
The cost of the paid accelerator depends on the network load, cryptocurrency prices and, according to the service description, ‘other factors’.
- BTC Nitro
BTC Nitro is another accelerator that offers two types of acceleration. With no reward staked, it simply relays the transaction to the network. For the equivalent of USD 25, it can include it in the next block mined by its partner pools. BTC Nitro guarantees confirmation of the transaction within 24 hours, failing which it promises to return the commission to the user.
- BitAccelerate
A free service that relays the transaction through 10 public nodes. The service's creators recommend using it for stuck transactions every six hours.
How to use a transaction accelerator
- Identify transaction delay
- Check the status of your transaction using a blockchain explorer.
- If it remains unconfirmed for a significant time, consider using an accelerator.
- Choose an accelerator
- Select a reliable transaction accelerator service.
- Paid services generally offer better performance and reliability.
- Submit Transaction ID
- Enter your transaction ID into the accelerator's form.
- For paid services, you will need to complete the payment.
- Wait for confirmation
- Once submitted, the accelerator will work to include your transaction in the next block.
- Check your transaction status periodically to see if it has been confirmed.
Conclusion
Accelerators can significantly reduce the time it takes for transactions to be confirmed. Most accelerators are straightforward to use, requiring only the transaction ID and, for paid services, a small fee. However, paid accelerators incur additional costs, which might concern frequent users. End even paid transaction accelerators may not guarantee immediate confirmation during extreme congestion.
Important! Do a basic background check before using paid accelerators (especially those you aren’t familiar with). Look for the domain registration date and reviews on forums. There have already been cases of fraudsters hiding behind accelerators. One example is Confirmtx, a service successfully launched in 2017, was reviewed several times and featured in several articles, and then caught committing fraud. The owners, of course, were collecting the money without accelerating anything.