<blockquote>
<p>If I have a single UTXO of value 10,000 sats and I'm using this as an input for a Segwit tx, then when I'm ready to sign the transaction / create the witness section, I use 10,000 as the value? Or is the value the sum of the outputs that I'm sending?</p>
</blockquote>
<p>You use 10000 as the amount and don't care about what other inputs are or how much their value is.</p>
<blockquote>
<p>Where does the 0046c32300000000 amount (600,000,000 in Decimal) come from?</p>
</blockquote>
<p>The &quot;amount&quot; that is being used during signing (and pretty much everywhere else) is always in satoshi as a 64-bit integer. Since the second input being signed had a value of 6 BTC that is equal to 600000000 satoshi. Which is the full value of the input (UTXO) that is being spent.</p>

CC BY-SA 4.0
2020-10-22T15:47:36.517Z
2020-10-22T15:47:36.517Z
Coding Enthusiast
<p>The BIP143 <a href="https://github.com/bitcoin/bips/blob/master/bip-0143.mediawiki#specification" rel="nofollow noreferrer">docs</a> state that the value is: &quot;value of the output spent by this input (8-byte little endian)&quot;</p>
<p>If I have a single UTXO of value 10,000 sats and I'm using this as an input for a Segwit tx, then when I'm ready to sign the transaction / create the witness section, I use 10,000 as the value? Or is the value the sum of the outputs that I'm sending?</p>
<p>Another example would be this in the BIP <a href="https://github.com/bitcoin/bips/blob/master/bip-0143.mediawiki#Native_P2WPKH" rel="nofollow noreferrer">example</a>.</p>
<p>Where does the <code>0046c32300000000</code> amount (600,000,000 in Decimal) come from?</p>
<p><a href="https://bitcoin.stackexchange.com/questions/61290/what-is-ment-by-the-value-of-the-output-spent-by-this-input-in-bip-143?rq=1">This</a> would suggest the &quot;value&quot; is the full available amount of that particular input? Or is it the amount of all the inputs combined?</p>

<transactions><segregated-witness><signature><message-signing>
What is the "value" in a Segwit sig hash?
Kyle
# What is the "value" in a Segwit sig hash?

(Asked by: username_0 on 2020-10-22)

The BIP143 [docs](https://github.com/bitcoin/bips/blob/master/bip-0143.mediawiki#specification) state that the value is: "value of the output spent by this input (8-byte little endian)"

If I have a single UTXO of value 10,000 sats and I'm using this as an input for a Segwit tx, then when I'm ready to sign the transaction / create the witness section, I use 10,000 as the value? Or is the value the sum of the outputs that I'm sending?

Another example would be this in the BIP [example](https://github.com/bitcoin/bips/blob/master/bip-0143.mediawiki#Native_P2WPKH).

Where does the `0046c32300000000` amount (600,000,000 in Decimal) come from?

[This](https://bitcoin.stackexchange.com/questions/61290/what-is-ment-by-the-value-of-the-output-spent-by-this-input-in-bip-143?rq=1) would suggest the "value" is the full available amount of that particular input? Or is it the amount of all the inputs combined?

**Tags:** transactions, segregated-witness, signature, message-signing


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## 1 answers

### Answer by username_1 on 2020-10-22. Score: 2 | Accepted answer

> If I have a single UTXO of value 10,000 sats and I'm using this as an input for a Segwit tx, then when I'm ready to sign the transaction / create the witness section, I use 10,000 as the value? Or is the value the sum of the outputs that I'm sending?

You use 10000 as the amount and don't care about what other inputs are or how much their value is.

> Where does the 0046c32300000000 amount (600,000,000 in Decimal) come from?

The "amount" that is being used during signing (and pretty much everywhere else) is always in satoshi as a 64-bit integer. Since the second input being signed had a value of 6 BTC that is equal to 600000000 satoshi. Which is the full value of the input (UTXO) that is being spent.


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