Confirmations correspond to the number of blocks that are dependent on a given transaction. This includes the block containing that transaction and all blocks after it in the blockchain. The more confirmations a transaction has, the more likely is it that it will remain in the blockchain permanently.
Questions tagged [confirmations]
251 questions
164
votes
11 answers
Why is my transaction not getting confirmed and what can I do about it?
I sent a transaction
without (or with an exceptionally small) transaction fee
using extremely small or unconfirmed inputs
while the stars were not standing right.
For whatever reason, I have been waiting forever for my transaction to confirm.
Why…
Avram
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5 answers
Why is 6 the number of confirms that is considered secure?
Why is 6 is the number of confirmations that is considered secure? I haven't found any mathematical explanation or otherwise that explains why it is 6 and not 5 or 7. Is there a historical reason for 6? Is there a specific way to calculate it so 6…
osmosis
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59
votes
3 answers
What are bitcoin "confirmations"?
When I receive bitcoins I see a certain number of "confirmations" in the client. What do these mean? Why do most sites make me wait for 6 "confirmations" before a purchase will go through?
lemonginger
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42
votes
8 answers
Can bitcoin exist without miners?
In the past year only, the bitcoin mining difficulty has increased fivefold. If in the coming years the difficulty increases so much that mining is no longer profitable (i.e. consumes more power than money is earned), can the bitcoin network exist…
Eduard Avetisyan
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40
votes
5 answers
How do I accept bitcoin payments at a real world store?
From what I understand, there are some requirements for using bitcoins at a physical store:
Both the store owner and the client must have Internet access
The client must have a cellphone or a laptop to issue the payment
The seller must have a way…
nmat
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39
votes
2 answers
What are Green Addresses?
What are Green Addresses? Is it true that they can solve the "confirmation delay" problem, and how does that work? Are there any drawbacks?
Thilo
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29
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5 answers
Has there ever been a successful double spend attack on the Bitcoin network? If not, is it really necessary to wait for confirmations?
There is a lot of concern about waiting for confirmations to avoid a double spend attack, but has there ever actually been a double spend attack?
It seems to be that there are two types of double spend attack. One is perpetrated without a…
Isaac Kriegman
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- 3
22
votes
4 answers
What happens if your transaction is never confirmed?
If I have a low amount and don't include a fee, the transaction takes forever to get confirmed. What happens if it never gets confirmed? Can the wallet that I sent it to still spend the money?
Ryan Detzel
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20
votes
6 answers
Recipient has “not received” the Bitcoin I sent, but the transaction is confirmed
I sent bitcoins to the address I was given (double checked). The recipient is claiming they did not receive it. I sent them a different payment yesterday at 8:30p and they didn't get it until 4:00am so could there be a lag also with this payment? Or…
Cccc1234
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19
votes
4 answers
Shortest and Longest block interval time ever recorded in Bitcoin
Bitcoin block interval time is on average 10 minutes, that is the difficulty is adjusted in such a way that every 10 minutes a miner will manage to find the right hash. This is just an average time though, the actual distribution for time…
Rexcirus
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19
votes
2 answers
What happens if my transaction is not accepted because I did not pay fees?
I was reading this thread about a client fork that does not force transaction fees and I noticed the big red warning saying that some coins might get lost if I am not careful. What does this mean? What should I do if my transaction is not accepted?
nmat
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18
votes
3 answers
How many confirmations do I need to ensure a transaction is successful?
As a regular user of Bitcoin, I often send bitcoins to other, or receive BTC from others, sometimes this might be a trade or deposit. Some traders require at least 6 confirmation, some require at least 3.
I want to how many confirmation is enough to…
HackFisher
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13
votes
1 answer
With 100% segwit transactions, what would be the max number of transaction confirmation possible on a block?
With 100% segwit transactions, what would be the max number of transaction confirmation possible on a block?
And, how many utxo can be updated by a block full of segwit transactions?
vi.su.
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13
votes
2 answers
How to minimize risk when accepting zero confirmation payments?
I'm trying to setup a way of accepting Bitcoin payments in real life situations, where waiting for confirmations is typically not an option. I understand this is never 100% risk free (especially with crap like bitundo.com around), I just want to…
RocketNuts
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12
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1 answer
How do Bitcoin clients determine the number of confirmations a transaction has?
The protocol specification doesn't seem to address this.
ashrewdmint
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