1
Generally the fee is based on tx size in the wallets I am aware of. Is there any wallet that allows setting fee based on a fixed fraction of total input value (say, 1/1000th of the inputs value)?
Please include wallets used by developers also (Bitcoinj, bitcoinjs, etc).
3
Most wallets that allow you to specify a custom fee would support this, technically. The fee is simply totalInput , totalOutput, so you can easily adjust it a fair bit.
However, miner's select txs based on sat/byte. In the system you described, some txs will end up severely underprices, while others will be massively overpriced.
Wallets currently just take the size of your tx, multiply it by a fee rate, and deduct that from the change outputs. This ensures that you are paying a fair fee for the tx size.
3
Is there any wallet that allows setting fee based on a fixed fraction of total input value (say, 1/1000th of the inputs value)?
I don't know of any that do (besides by allowing you to manually set the fee), because it doesn't make sense.
Prioritization of your transaction in the network is based on their weight (~size), not the value being transferred. The value being transferred isn't even always possible to infer from the transaction (for privacy reasons). A wallet that would set a fee based on amount would be letting the user seriously shoot themselves in the foot.
