Linked Questions

18
votes
3answers
85k views

How many confirmations do I need to ensure a transaction is successful? [duplicate]

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 ...
-1
votes
1answer
244 views

Can I spend a tx before it has 6 confirmations? [duplicate]

When I got a transaction (someone transfer some bitcoins to me), can I use it before the transaction has 6 confirmations?
58
votes
2answers
91k views

Can someone explain how the Bitcoin Blockchain works?

I'm trying to figure out how the blockchain works and how to read it via blockchain.info website. Is there a laymen way of explaining how the block chain works and how to read the blockchain to trace ...
44
votes
4answers
16k views

Why was the target block time chosen to be 10 minutes?

According to the wiki, 10 minutes was chosen as a 'tradeoff'. Why ten minutes specifically? It is a tradeoff chosen by Satoshi between propagation time of new blocks in large networks and the ...
8
votes
4answers
6k views

Will transaction confirmation time be reduced as the network size increases?

Right now it takes 6 confirmations, which takes about an hour to verify a transaction. Will the rate at which transactions confirm become faster over time?
7
votes
1answer
2k views

Why do mining pools require 120 confirms for a solved block before payout?

According to this question here, 6 confirmations can be considered 'secure enough'. Some pools out there also offer payout at 100 confirms but that's still substantially higher than 6. Why is such a ...
-1
votes
1answer
6k views

How many confirmations takes place before transaction is successful

Yesterday I attempted to send two bitcoin transfers from Livecoin and almost 24 hours later it hasn't been successful. When I check the transactions they have 99 and 95 confirmations. What does that ...
1
vote
1answer
900 views

What is the risk of waiting for just one confirmation to validate a transaction, assuming the counterparty is not a miner?

I am trying to determine how many confirmations would be reasonably safe to wait before accepting a Bitcoin transaction from an attacker that is not a miner and hence cannot rely on Finney attacks, ...
1
vote
2answers
338 views

What's so special about six blocks for confirming transactions?

I read that when your transaction is part of a block that has five other blocks on top of it, you can feel safe that your transaction is not in danger of being orphaned because someone else would come ...
0
votes
2answers
69 views

Can two or more transactions sent from the same address be mined in the same block in Bitcoin's blockchain?

Imagine a person Bob has 10 bitcoins in his wallet. He wants to send 5 bitcoins to Alice and another 5 bitcoins to Uncle Tom simultaneously (in separate transactions). Will both Bob's transactions be ...
0
votes
2answers
150 views

How long a high-priority transaction takes to evaluate

I am missing something so far in reading this (excellent resource). I read the part about transactions for the most part, but I don't understand the actual code evaluation part, and how long it takes. ...
0
votes
1answer
122 views

Detection of double spend in Bitcoin for aged transactions

This is just to verify my understanding of Bitcoin double spend detection. 1) Use of UTXO indexes : This ensures that there as been no spend from that output (transferred to recipient in Block of ...
0
votes
1answer
104 views

How long should I wait to consider that the transation is “definitely” confirmed?

When one transaction is broadcasted, what is the probability that it won't be confirmed? (By probability, I mean the observed probability on the blockchain. If a person intentionally spend twice 1 ...
0
votes
2answers
71 views

How could a lightweight wallet determine the validity of 0-conf transaction?

I found that a lot of people are interested about security of 0-confirmation payments. But, it seems that most discussions focused on double-spending (like broadcasting two or more conflicting-but-...
1
vote
1answer
68 views

bitcoin reorg question

if a block takes 10 minutes to be mined does it need 21 minutes to be reorged? if the reorg started immediately after the block was mined because 100% was mining and 51.5% will reorg how long does ...