Questions about some details on Ethereum transfers and Gwei

Question

I read up about Gas and Gwei but there are some things in practice that i don't understand / know what to do. I just started learning about Ethereum (received my first ETH coins today and started using Metamask and exchange markets( GDAX, Kucoin). Here are some questions i can't seem to figure out or be sure on my own...

When i transferred varying amounts of ETH from GDAX to Kucoin, the Gwei seems to be automatically set at 100+ (110 to 122). My understanding is that that is a pretty high Gwei and is not necessary. I can't seem to figure out how to adjust the Gwei value though. Is there a market exchange specific setting to adjust Gwei for xfering ETH?

Does the transfer fee vary at all depending on the amount of ETH transferred? I thought it would make sense for it to vary, but what i find is that i pay the same amount of fee even when i transfer a small amount of ETH.

The "Gas Used" amount also seems to remain constant for any amount of ETH xfer i tried (at 21,000). Is this a value that i can adjust? Or is it always set like this?

Well... maybe not just an ETH question but.. i'm missing a transfer i made to KuCoin. Since that particular xfer wasn't showing up on my Kucoin account, i went to Etherchain.org to check up using the transaction hash. It shows everything was ok: correct wallet address, 1819 confirmations in green text, confirmed in 58 seconds, etc... everything seems fine. But that xfer just hasn't been made into Kucoin. Is this a not-so-uncommon problem that has to do with Kucoin (like they somehow "lost" the incoming transfer or something)? How would you resolve such issues?

The whole Gas usage and Gwei thing seem a bit confusing... It seems though.. is Bitcoin more expensive when transferring? Also, the transfer fee doesn't depend on the amount you transfer, is that correct? This seems a bit.. unreasonable to me as a newbie, but i suppose there are reasons developers made it like that.. Is it always a better idea to transfer a large amount of ETH / BTC at once, instead of small amounts in multiple transactions?

Many noob questions.. hope you're not annoyed :) Thank you

Answer 1

• When i transferred varying amounts of ETH from GDAX to Kucoin, the Gwei seems to be automatically set at 100+ (110 to 122). My understanding is that that is a pretty high Gwei and is not necessary. I can't seem to figure out how to adjust the Gwei value though. Is there a market exchange specific setting to adjust Gwei for xfering ETH?

The "GWei" is actually called gas Price. It is the amount of ether you accept to pay for each gas consumed. The higher it is, the faster your transaction will be mined (to explain it in a simple way). But you can set this value as you want (Using Mist, Myetherwallet, etc).

• The "Gas Used" amount also seems to remain constant for any amount of ETH xfer i tried (at 21,000). Is this a value that i can adjust? Or is it always set like this?

You cannot adjust it. It is established by the ethereum virtual machine. 21k is the very minimum for a transaction (basically, a simple ether transer will always be 21k gas). As a user, you want this value to be as small as possible to not pay to much.

• Is this a not-so-uncommon problem that has to do with Kucoin (like they somehow "lost" the incoming transfer or something)? How would you resolve such issues?

Need more details about what you are trying to achieve.

• Is it always a better idea to transfer a large amount of ETH / BTC at once, instead of small amounts in multiple transactions?

(My answer is for ethereum only, bitcoin works in a (very?) different way) Yes. Because one tx costs AT LEAST 21k gas. So if you transfer 10 eth in 10 tx (1 by 1), you will pay 21k * 10 + (additionnal contract gas needed for processing). If you do it once, you pay 21k * 1 + (additionnal gas needed by the contract).

• Also, the transfer fee doesn't depend on the amount you transfer, is that correct?

Yes. The tx fees depend on gas, not on amount of token/eth transferred

• What is gas, how does it work?

A transaction has 4 properties related to gas:

1. gasLimit: The maximum amount of gas you accept to use. This is an internal security to avoid infinite loops and then potentialy infinite costs
2. gasCost: The actual amount of gas used. If it used less gas than the gas limit value, you get charged only for gas used.
3. gasPrice: The value in ether for a unit of gas.
4. txFee: This is the actual fees you paid for the tx, it is: gasPrice * (gasCost + 21 000)

Answer 2

Is there a market exchange specific setting to adjust Gwei for xfering ETH?

Before sending a transaction, it is possible to set the max transfer fee you are willing to pay. The higher the fee, the faster your transaction will be processed. If you use your own ethereum wallet (myetherwallet, mist, metamask...) you will be able to set this option*. However, in cases of exchanges, it depends how the exchange implemented their user inferface. Maybe that some exchanges just pre-select a default value for transaction fees and dont allow users to change it?

*Technically you cant directly specify the maximum fee you are willing to pay. What happen is that you specify what is the maximum units of computational steps this transaction is allowed to consume (gas), and how much units of ether you are willing to pay for each unit of gas spent. Some wallets make it easy for users and just show a transaction fees setting, but behing the hood they set the gas and gasprice and send those info along the transaction to the network.

Does the transfer fee vary at all depending on the amount of ETH transferred?

No. It varies depending on the gas price (how much you are willing to pay per computational step) and the gas consumption of your transaction (i.e simple ether transfers are cheaper than complex smart contract execution)

Is Bitcoin more expensive when transferring?

Definetly. The bitcoin fees are currently of 50usd for a transaction:

https://bitinfocharts.com/comparison/bitcoin-transactionfees.html

Whereas it is "only" 4 usd currently for ethereum:

https://bitinfocharts.com/comparison/ethereum-transactionfees.html