<p>Block timestamps are whatever time the miner wants to put in there, within some loose bounds, so there isn't a real guarantee.</p>

<p>For more info on what those bounds are, check out this answer:</p>

<ul>
<li><a href="https://bitcoin.stackexchange.com/a/917/18196">https://bitcoin.stackexchange.com/a/917/18196</a></li>
</ul>

CC BY-SA 3.0
2017-03-24T17:54:28.173Z
2017-03-24T17:54:28.173Z
2017-04-13T12:47:33.610Z
morsecoder
<p>In the <a href="https://en.bitcoin.it/wiki/Block_timestamp" rel="nofollow noreferrer">Bitcoin wiki</a>:</p>

<blockquote>
  <p>Block times are accurate only to within an hour or two.</p>
</blockquote>

<p>is a bit vague. Is it possible to prove that an arbitrary accepted block timestamp is within x seconds of the real-world time? How?</p>

CC BY-SA 3.0
2017-03-24T17:51:20.323Z
What would you even want that time to be? The time that the block was assembled, or the time that it was solved, or the time it was seen by the network?
morsecoder
CC BY-SA 3.0
2017-03-24T21:30:27.013Z
@StephenM347 for example, in this answer http://bitcoin.stackexchange.com/a/29555/21671 the answer of `bitcoind getrawtransaction` returns a `blocktime` field, along the others (vin, vout, etc). I mean that "block time".
Victor
CC BY-SA 3.0
2017-03-27T15:43:48.347Z
I know what field you're talking about, I'm not clear on what information you would want to be put in that field.
morsecoder
<timestamp>
Proving the margin of error of a block timestamp
Victor
# Proving the margin of error of a block timestamp

(Asked by: username_0 on 2017-03-24)

In the [Bitcoin wiki](https://en.bitcoin.it/wiki/Block_timestamp):

> Block times are accurate only to within an hour or two.

is a bit vague. Is it possible to prove that an arbitrary accepted block timestamp is within x seconds of the real-world time? How?

**Tags:** timestamp

> **Comments:**
> **username_1**: What would you even want that time to be? The time that the block was assembled, or the time that it was solved, or the time it was seen by the network?  
> **username_0**: @StephenM347 for example, in this answer http://bitcoin.stackexchange.com/a/29555/21671 the answer of `bitcoind getrawtransaction` returns a `blocktime` field, along the others (vin, vout, etc). I mean that "block time".  
> **username_1**: I know what field you're talking about, I'm not clear on what information you would want to be put in that field.  

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## 1 answers

### Answer by username_1 on 2017-03-24. Score: 1

Block timestamps are whatever time the miner wants to put in there, within some loose bounds, so there isn't a real guarantee.

For more info on what those bounds are, check out this answer:

* <https://bitcoin.stackexchange.com/a/917/18196>


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