It may worth mentioning that the fee they charge you for accelerating your transaction doesn't depend on the amount of bitcoin you send.


ViaBTC was the only working free accelerator until bots made it useless.
All other websites that claim to accelerate transactions freely, are either scammers or just rebroadcast transactions.

Even bitcoin.org itself recommends checking bitcoincore.org to make sure you are downloading the latest version.

It seems that they stop accepting new transactions once they reach a certain size of transactions waiting to be mined freely.
Of course, nothing has been mentioned on their website and I don't know the exact amount. I just know that it should happen very rarely. ViaBTC has around 10% of the total hash rate and it's estimated that they mine 1 block in every ~ 100 minutes on average.


They could accept more transactions, but it seems that they don't allocate the space of each block more than a certain amount to freely accelerated  transactions.

ViaBTC didn't mine any block between 00:00  and 09:05 UTC and I think they stopped accepting new transactions once they reached a certain size of transactions waiting to be mined freely.

I made a post about this in another thread.
Re: ViaBTC offers no more free TX acceleration?

Yes, they are bypassing the captcha.
Bots solve ViaBTC captcha faster than humans.


I just checked that and it's still displaying 19 remaining hourly free transactions.

ViaBTC hasn't mined any block in the past 9 hours.
I guess they won't accept any new transaction for free acceleration until they mine a new block and include the transactions they have received in the past 9 hours.


Edit:
It seems that my guess was correct.
ViaBTC just mined a block and they accepted more transactions for free acceleration after that.
The number of remaining hourly free transactions is now zero.

They are still accelerating 100 transactions per hour freely.
The problem is that ordinal scammers are abusing ViaBTC free accelerator with their bots and don't allow humans to submit their transactions.

If you check the last blocks mined by ViaBTC, you will see that they have included many low fee transactions.

Read the post I made in another thread.

Can I ask you what exactly you worry about? Do you think your wallet may be compromised?

Note that you can replace a transaction with a new one only if you have the private key of one of receiving addresses. If your wallet is compromised, your fund can be stolen right now.
And even if you broadcast a RBF-disabled transaction, as long as it's unconfirmed, anyone who has access to your private key may be able to replace that with a new one.

I think they do.

Here are the latest two blocks mined by ViaBTC. Transactions are sorted by their fee rate in ascending order.
(Times are in UTC.)

• 823055 (19:31)
• 823066 (22:01)

Just visit the above links and see how many low fee transactions they have included.


According to above times, ViaBTC should have accelerated 300 transactions freely in block number 823066.
Let's check if they did so.


The minimum required fee rate for getting confirmation in block number 823066 was around 100 satoshi. ViaBTC included 312 transactions with the fee rate of less than 90 sat/vbyte. Click here to see all those transactions.
10 out of those 312 transactions were confirmed with CPFP and that means that 302 transactions were accelerated by ViaBTC. All those 302 transactions meet ViaBTC free accelerator requirements.

The problem is how ViaBTC free accelerator is being abused by bots. 294 out of 302 transactions are related to ordinals. They are all 1 input - 1 output transactions paying 23 sat/vbyte.

Username: hosseinimr93
Segwit Bitcoin address: bc1qq469jmsttgwju04fkzft8fhh7lged0r2hgn7xm

Again, what matters is the fee rate and that's what miners prioritize transactions based on.
The total fee you pay for a transaction is equal to virtual size of transaction (in vbyte) multiplied by fee rate (in sat/vbyte) and it doesn't matter how much bitcoin you send. The (virtual) size of the transaction depends on number of inputs and outputs and addresses types.


Let's say you want to make a transaction including 100 legacy inputs and 1 output. Your transaction would be around 14,700 vbyte in (virtual) size.
If you are not in a hurry and you make the transaction with the fee rate of only 20 sat/vbyte, it would cost you more than $120 worth of bitcoin.

It's possible that most of the nodes drop your transaction from their mempool, but there is no guarantee that it won't be confirmed.
As long as there is no other confirmed transaction invalidating that transaction, there's a chance that the transaction is confirmed.

If you have broadcasted a transaction and you want to make sure that it won't be confirmed, you must create a new transaction using the same input and invalidate that.
Provided that the transaction is still valid, it may be confirmed one day even if you broadcasted it months ago and your wallet doesn't show it anymore.

If they change the captcha, those spammers will probably find a way to bypass the captcha again.
They may add an extra requirement and not allow transactions that create output worth less than a certain amount to be submitted to their free accelerator.

The sad news is that those bots have been created by ordinal scammers.

I just checked one of the blocks mined by ViaBTC recently on blockchair.com and sorted the transactions by their fee rate. (Click here.)
In block number 822736, the required fee rate to get confirmation normally was 72 sat/vbyte. ViaBTC included 110 transactions with the fee rate of less than 70 sat/vbyte. 95 of them were 1 input - 1 output transactions sending 294, 330 or 546 satoshi paying 23 sat/vbyte.

I checked the 15 other transactions one by one. 11 of them were larger than 500 bytes in size and it's not possible that they have been submitted to ViaBTC free accelerator. 2 out of the 4 remaining transactions were confirmed with doing CPFP. In block 822,736 which was mined ViaBTC, there were only 2 normal transactions that may have been confirmed with the help of their free accelerator.

Making another withdrawal from cashapp doesn't affect your unconfirmed transaction and that's useless.

Nothing will change after 14 days.
Many nodes will still keep the transaction in their mempool and cashapp may rebroadcast the transaction.


Do you have control over the receiving address? If so, you can do CPFP.
CPFP means spending the fund received in the unconfirmed transaction with high fee in a new transaction, so that miners include both transactions in the same block.

If you are referring to an individual private key, you can derive three types of addresses.

Select "Import addresses or private keys" when creating a new wallet and add a prefix to specify the address type.

Use "p2pkh" for generating a legacy address.
Use "p2wpkh-p2sh" for generating a nested segwit address.
Use "p2wpkh" for generating a native segwit address.

For example, if you want to generate a native segwit address, you should enter your private key as follows.




To be more accurate, this command increases the gap limit.
For example, if you set the gap limit to 200, electrum will generate more and more addresses and display their transactions history until it reaches 200 consecutive unused addresses.



new19980, you can also use the following command to generate more addresses without increasing the gap limit.

This command generates 50 more addresses without increasing the gap limit.

Most wallets use standard derivation paths.


m/44'/0'/0' is usually used for generating legacy addresses and the first receiving legacy address is generated at m/44'/0'/0'/0/0
m/49'/0'/0' is usually used for generating nested segwit addresses and the first receiving nested segwit address is generated at m/49'/0'/0'/0/0   
m/84'/0'/0' is usually used for generating native segwit addresses and the first receiving native segwit address is generated at m/84'/0'/0'/0/0   


For example, if you import a BIP39 seed phrase in electrum (without changing the derivation path) to generate a native segwit wallet, by default it gives you 20 receiving addresses and 10 change addresses.
The 20 receiving addresses would be generated at m/84'/0'/0'/0/0 - m/84'/0'/0'/0/19 and the 10 change addresses would be generated at m/84'/0'/0'/1/0 - m/84'/0'/0'/1/19


In the case you have generated your addresses using a non-standard derivation path for any reason, you need to know the derivation path as well and you still don't need to save individual private keys.

If you have a seed phrase (which is a series of words and it's also called mnemonic phrase), you don't need to keep individual private keys and that's one of advantages of having a HD wallet with seed phrase.
Note that your seed phrase can generate all your private keys and that's all you need.

Let's say we have a bitcoin wallet generated using the standard derivation path of m/44'/0'/0' and addresses are generated at m/44'/0'/0'/x/y. (x is the change index and y is the address index).

If we only change the address index, we can generate 2^32 addresses. The address index can be in the range of 0 to  2^32 -1 (or 0xFFFFFFFF in hexadecimal system).
If we change the change index as well, we can have 2^33 addresses. The change index can be either 0 or 1.


We can also generate addresses using non-standard derivation paths with changing the account index. We can generate addresses using the derivation path of m/44'/0'/1', m/44'/0'/2' and so on.
Like the address index, the account index can be also in the range of 0 to 2^32 - 1.

With changing the account index, the change index and the address index, we can generate 2^65 addresses.


We can also generate more addresses with using BIP49 and BIP84 standards.
If we consider the three BIP44, BIP49 and BIP84 standards, we can generate 3 * 2^65 addresses.


We can still generate more addresses with using more complicated non-standard derivation paths.

If you had sent the fund to your own wallet and you had the private key, you would be able to do CPFP, but you had to pay a very big fee for the CPFP transaction.

The network has become less congested and now around 90 sat/vbyte is required for getting confirmation. To increase the effective fee rate of your transaction to 90 sat/vbyte, you would have to pay around 0.025 BTC for the CPFP transaction.
Would you pay that high fee, if you could do CPFP?

Technically, it's possible for coinbase to do CPFP and make your transaction confirmed, but they will never do that.
Why should they pay the fee for your deposit?

Provided that the transaction hash you sent me via pm is correct, they are wrong.

Enter your transaction hash on mempool.space to see your transaction.
After that, click on the red button beside the sending address to see the unconfirmed parent. Do the same thing to see older unconfirmed transactions.