Get real fee per transaction

1

I am trying to get real fee per trasnaction.

So I have an account whit balance 0.06940000 and have a second account with balance 0.00000000.

To get current fee I have run the command

bitcoin-cli getmempoolinfo

and got the mempoolminfee = 0.00001000. I thought that when I send the 0.06939000 in my account rest balance will 0.00000000. but I got 0.00004860. Actually the fee was 0.0000514.

general question is WhY ?

Please tell me to understand how is fees working!

Yur Gasparyan

Posted 2018-10-01T12:12:56.813

Reputation: 181

Answers

1

What getmempoolinfo is returning is not the minimum fee to send a transaction, but the minimum rate per kilobyte to send a transaction. Your bitcoin client will take the configured fee and multiply it by the size of the transaction in kilobytes to calculate the actual transaction fee.

The size of a transaction is somewhat difficult to compute (for a person) because it requires understanding the number of inputs that are required to fulfil the transaction, the number of outputs (primary recipients + change address), and the targeted transaction fee (since appropriate fees could eliminate the need for a change address).

There are online fee calculators out there you can use to estimate these, but it is still difficult to completely empty a wallet with a known fee using the straight bitcoin client.

Motoma

Posted 2018-10-01T12:12:56.813

Reputation: 161

Is there a way to get fee before sending transaction ?Yur Gasparyan 2018-10-01T13:03:43.580

No, but if all you are looking to do is empty a wallet, you can pass an argument to sendtoaddress which will take the fee out of the sent amount rather than the wallet you're sending from--you will receive less bitcoin than you "sent", but you will be able to empty the wallet.

See argument #5 for sendtoaddress: https://bitcoin.org/en/developer-reference#sendtoaddress

Motoma 2018-10-01T13:09:58.823

thanks! but what when i want to send bitcoins from specific account to address?Yur Gasparyan 2018-10-01T13:16:18.770

Again, if you want to remove a specific amount from the sending address, you set that 5th argument to true. If you want a specific amount to be received by the recipient address, you leave it set to false.Motoma 2018-10-01T13:31:42.377