<p>When you pay with bitcoin using a service that uses Coinbase as a payment processor (such as Humble Bundle), it usually accepts in a short amount of time. The reason they can do this is because they check that your transaction has propagated through the whole network and that there are no competing (double spend) transactions.</p>

<p>Once that has happened, the only way to do a double spend is to mine your own block (because everyone else has accepted your first transaction). Mining a block is very expensive so there is very low risk. Certainly less than the risk of credit card chargebacks. </p>

<p>Now if you are selling something very expensive, then waiting for some confirmations would be good. Also in this case the buyer would likely be in less of a hurry.</p>

CC BY-SA 3.0
2014-06-30T16:09:23.773Z
That's a good point. Some random person making a small transaction at a retail store or similar is exceedingly unlikely to have access to the computing power to mount a Finney attack and anyone who could would be so rich that using the attack to save $60 wouldn't be worth it. So for small transactions, network monitoring probably is enough.
Tyler
CC BY-SA 3.0
2014-06-30T04:01:58.973Z
2014-06-30T04:01:58.973Z
Buge
<p>If bitcoin is ever going to be mainstream, how can we get around the problem of confirmation time? I don't think I like the idea of having to wait an hour for my transaction to be confirmed so I can leave the gas station after filling up. Even with the usual recommendation of waiting for only one confirmation, that's still 10 minutes. Anything over 10 or 20 seconds becomes a problem if all customers are using bitcoin, because it delays <em>every</em> transaction that long.</p>

CC BY-SA 3.0
2014-06-29T03:37:13.713Z
One possible solution is called Green Addresses. See https://en.bitcoin.it/wiki/Green_address
DJG
<confirmations>
How can bitcoin be used for all transactions, even with only one confirmation?
Tyler
# How can bitcoin be used for all transactions, even with only one confirmation?

(Asked by: username_0 on 2014-06-28)

If bitcoin is ever going to be mainstream, how can we get around the problem of confirmation time? I don't think I like the idea of having to wait an hour for my transaction to be confirmed so I can leave the gas station after filling up. Even with the usual recommendation of waiting for only one confirmation, that's still 10 minutes. Anything over 10 or 20 seconds becomes a problem if all customers are using bitcoin, because it delays *every* transaction that long.

**Tags:** confirmations

> **Comments:**
> **username_1**: One possible solution is called Green Addresses. See https://en.bitcoin.it/wiki/Green_address  

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## 1 answers

### Answer by username_2 on 2014-06-30. Score: 1 | Accepted answer

When you pay with bitcoin using a service that uses Coinbase as a payment processor (such as Humble Bundle), it usually accepts in a short amount of time. The reason they can do this is because they check that your transaction has propagated through the whole network and that there are no competing (double spend) transactions.

Once that has happened, the only way to do a double spend is to mine your own block (because everyone else has accepted your first transaction). Mining a block is very expensive so there is very low risk. Certainly less than the risk of credit card chargebacks.

Now if you are selling something very expensive, then waiting for some confirmations would be good. Also in this case the buyer would likely be in less of a hurry.

> **Comments:**
> **username_0**: That's a good point. Some random person making a small transaction at a retail store or similar is exceedingly unlikely to have access to the computing power to mount a Finney attack and anyone who could would be so rich that using the attack to save $60 wouldn't be worth it. So for small transactions, network monitoring probably is enough.  

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