Author

Topic: Bitcoin Confirmations Question (Read 205 times)

legendary
Activity: 2730
Merit: 7065
March 31, 2021, 02:12:15 AM
#10
Unless you are dealing with tens of thousands of dollars, 1 confirmation is enough most of the times. Just make sure the transaction gets its first confirmation before you send your coins if that is the agreement you made with the other party.

I think that the default Ledger Live settings consider a bitcoin transaction confirmed after it has 2 blockchain confirmations. You can check how it is for Litecoin and USDT in the settings of your LL and just use that as a reference point. I think you need to click on Settings > Currencies and there you can inspect and even adjust the confirmation times for each coin separately.    
legendary
Activity: 1624
Merit: 2481
March 29, 2021, 06:32:18 AM
#9
Is it still the same amount of confirmations with btc right now even with the sending fees?

The amount of confirmations a transaction is considered to be final is completely independent from the fees.

Depending on the amount, 1 to 6 confirmations are enough.
legendary
Activity: 1624
Merit: 2481
December 29, 2020, 11:50:38 AM
#8
I heard of that double spending with btc.  So if someone sends me btc and say i send them cash or online funds... how do i make sure that transaction won't get double spend?  Imagine someone send me btc... it shows in my ledger live wallet but shows 0 confirmations... let say its a thousand dollars to make it simple.  How long do i need to wait... or how many confirmations do i need... before i send them a thousand dollars to be safe? 

At least one confirmation is enough for smaller amounts.
If you want to be on the super safe side, wait for 2 or 3 confirmations. More is really not necessary anymore.



Because i heard of cases where someone send btc to someone in exchange for wire transfer/cash ... but because of double spend... the receiver never gets the btc as transaction never gets confirmed... and they are out cash.  How do you counter against that?  Do you look at the transaction fee that person paid for the transfer or how?

That's simple. By waiting for at least 1 confirmation.
The fee is not that meaningful when speaking about double spending. The amount of confirmations are.

Wait for at least 1 confirmation and you are safe. It is (under given circumstances) possible to double spend transactions with a confirmation, but this is associated with costs of ~1 block reward (= 6.25 BTC) and a risk of failure.
HCP
legendary
Activity: 2086
Merit: 4361
December 28, 2020, 05:58:42 PM
#7
but how do you know the exact price you received it then for tax purposes? 
Again... there is no "exact" price... so you're asking for the "impossible" Roll Eyes The best you can do is approximate... There are services that offer historical BTC prices (usually averaged across major exchanges to flatten out localised dips/spikes), usually via API's etc... that's how most of the "price history" charts work.

How you choose to deal with that for "tax purposes" is up to your, your tax department and any rules they may enforce on calculating prices.


I heard of that double spending with btc.  So if someone sends me btc and say i send them cash or online funds... how do i make sure that transaction won't get double spend? 
...
How do you counter against that?  Do you look at the transaction fee that person paid for the transfer or how?
Transaction fee means nothing... The only thing you need to look for is number of confirmations.

Zero confirmations means exactly that... ZERO confirmations, the coins could still be theoretically double spent in another transaction with a higher fee. These days, with the current level of total hash power, executing a 51% attack is nearly impossible... at the very least it would be insanely expensive.

So, any non-zero number of confirmations (ie. 1 or more) means that the transaction is, for all intents and purposes, basically irreversible. If you're dealing in transactions of massive value (ie. $10s/$100s millions) you might want to wait for a few more like 3 or 6 etc.... but in general 1 confirmation should be enough and considered the absolute minimum.

Same with RBF... if someone sends an "RBF enabled" transaction, it should not be "trusted" until there is at least 1 confirmation. At that point, RBF cannot be used to "respend" coins.
full member
Activity: 1750
Merit: 186
December 28, 2020, 05:00:16 PM
#6
Hey hcp... well right now im only using the nano ledger s now... haven't used electrum in a while.


What i did notice earlier was when i check ledger live... the amount that is shown as received in USD under the btc received... is the same as yesterday.  But the day before that... it kept changing all day.


So it makes sense that with ledger live... after a day or so... the amount you received in price so to speak... that doesn't change in ledger live anymore right?  And yea i know when you receive it, its btc... not the amount ... you assign the amount... but how do you know the exact price you received it then for tax purposes?  Like do you count it as the moment it showed in your wallet even when it has 0 confirmations?  Or three confirmations?  Because even with 0 confirmations... you could still send that btc to someone else right?  I recall electrum you could do this a while back.


Another question i have is this.


I heard of that double spending with btc.  So if someone sends me btc and say i send them cash or online funds... how do i make sure that transaction won't get double spend?  Imagine someone send me btc... it shows in my ledger live wallet but shows 0 confirmations... let say its a thousand dollars to make it simple.  How long do i need to wait... or how many confirmations do i need... before i send them a thousand dollars to be safe?  Because i heard of cases where someone send btc to someone in exchange for wire transfer/cash ... but because of double spend... the receiver never gets the btc as transaction never gets confirmed... and they are out cash.  How do you counter against that?  Do you look at the transaction fee that person paid for the transfer or how?


HCP
legendary
Activity: 2086
Merit: 4361
December 27, 2020, 11:48:23 PM
#5
Also... if you look at it from this way, at what price exactly did you receive the btc at?  Because the amount of btc they sent to you at the time even though it shows 0 confirmations... well it will always get confirmed right?  Or there could be an issue like i heard about double spending a while back?  I assume you would calculate the price you received it at ... the moment you receive 3 confirmations or when the USD amount no longer change?
You don't receive btc at a fiat price... you receive a given amount of BTC... Roll Eyes What value you assign to that BTC is up to you.

The "price" is so volatile and varies across countries, exchanges, services etc... there is no definitive "This is the current value of BTC in " value. Explorers like blockchain.com that show a fiat value on transactions simply take a snapshot of the exchange price from some source (likely an exchange API) at the time the block is first mined.



Also could you send any btc from your wallet if the btc you received did not have confirmations or enough confirmations? 
If your wallet allows spending "unconfirmed coins"... some wallets do, some wallets don't...

Electrum has a specific setting:


Bitcoin Core has a setting specifically for change amounts generated ... but I'm fairly sure will allow you to spend unconfirmed coins that were "received" regardless of that setting:


legendary
Activity: 1596
Merit: 1288
December 27, 2020, 03:40:25 AM
#4
if you have some time watch this video https://www.youtube.com/watch?v=MPQMCVVhExY or search for  Andreas Antonopoulos xxx (what you want to know about bitcoin) on youtube.
Bitcoin is always equal to 1 BTC, but its value varies according to the price, so the amount is not supposed to change in bitcoin, but in dollars.

The cost of fees and confirmation times varies by network and the video above explains everything
legendary
Activity: 1904
Merit: 1563
December 27, 2020, 02:26:31 AM
#3
Also saw the fee as almost 7 dollars or so.  That is the fee that the site paid right?  Just want to make sure but im pretty sure.  Thats pretty high.  Is that the avg now?
Some websites charge their user's withdrawal for that certain amount of fee since most of them are doing batch payments for their clients or maybe to have at least some profit on their side. Most of the cryptocurrency exchange and gambling website are doing that similar process. More importantly, you can visit Johoe's Bitcoin Mempool Statistics to see how much sats you can spend to make a transaction.

At the time of writing this, you can spend a minimum of 2 sats/vbyte for your transaction to be included in the next block.

My assumption here is because it doesn't have enough confirmations... that is why the USD amount keeps changing in the history of transactions of ledger live?
The USD rate has nothing to do with the confirmation showing on the transaction details. The reason why the fiat value is constantly changing is primarily because of the supply and demand of the certain asset which in this case is BTC. On the other hand, "confirmation" tells you that your transaction has been verified and is included in a block. In layman's term, confirmation is a representation to tell whether your transaction is complete or not.
legendary
Activity: 1876
Merit: 3132
December 26, 2020, 04:54:38 PM
#2
Also saw the fee as almost 7 dollars or so.  That is the fee that the site paid right?  Just want to make sure but im pretty sure.  Thats pretty high.  Is that the avg now?

That depends on the transaction. If you were the only recipient then 7 dollars was an overkill. ~25 cents should be enough for a small (1 input; 1 output) to be confirmed in the next block.

I assume once it hit a certain amount of confirmations... then the USD amount that is shown for received under the amount of btc received would stay the same?

I use PLN instead of USD but it should not matter; the exchange rate changes every few minutes and the fiat value updates everywhere.

Also could you send any btc from your wallet if the btc you received did not have confirmations or enough confirmations?

Yes, that's how you perform CPFP by the way. Both Electrum and Ledger Live can do that. Some other wallets might not allow you do it, though.
full member
Activity: 1750
Merit: 186
December 26, 2020, 04:33:58 PM
#1
So I requested some btc from a site.  That site is pretty quick since after I requested a withdraw, the amount got deducted from my balance on that site... and i see the btc was sent to my nano ledger s wallet on ledger live.  At the time it did that, you see the amount of btc received and also the usd amount.  Then i notice minutes later, that usd amount kept changing over and over.  I clicked on transaction and noticed... status showed 0 confirmations.



Also saw the fee as almost 7 dollars or so.  That is the fee that the site paid right?  Just want to make sure but im pretty sure.  Thats pretty high.  Is that the avg now?



Now in previous transactions on ledger live, i recall those usd amounts that are shown in my transaction history such as amount of btc sent or received... the usd amount always stayed the same.



My assumption here is because it doesn't have enough confirmations... that is why the USD amount keeps changing in the history of transactions of ledger live?



I then clicked on the transaction and it shows 3 confirmations now.  I assume once it hit a certain amount of confirmations... then the USD amount that is shown for received under the amount of btc received would stay the same?  And is that number how many confirmations?  Because for like 5 minutes or so... that usd amount did not change at all.  But now it changed again.



Also... if you look at it from this way, at what price exactly did you receive the btc at?  Because the amount of btc they sent to you at the time even though it shows 0 confirmations... well it will always get confirmed right?  Or there could be an issue like i heard about double spending a while back?  I assume you would calculate the price you received it at ... the moment you receive 3 confirmations or when the USD amount no longer change?



Also could you send any btc from your wallet if the btc you received did not have confirmations or enough confirmations?  Obviously if you have say 1 btc and receive 0.01 btc and that btc isn't confirmed yet, well no big issue since you have enough btc in your wallet.  But what if you have 0 btc or say 1 btc and received 0.01 btc but there is either 0 confirmations or 3 confirmations... but now you want to send the whole 0.01 btc or say your entire balance of 1.01 btc etc.  Could you do that?


I remember with electrum, when i received some btc i would then immediately send it to another site with the amount of btc i just received... and i don't think it was an issue.  I think i might have done this even with 0 transactions and it worked but it took a while.  Can anyone confirm this?  Or it only works if it has say 3 confirmations or more?
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