<p>Depends on the software. You can construct a transaction that spends whichever utxos you want, so yes, you can send someone the exact amount of the sum of dust transactions. As for the transaction fee, the network may or may not relay, but even there, you may be able to get a friendly miner to mine it.</p>

CC BY-SA 3.0
2015-11-10T04:34:01.017Z
The question seems to be specifically asking about the behavior of Bitcoin Core and/or XT.
Nate Eldredge
CC BY-SA 3.0
2015-11-10T03:52:20.407Z
2015-11-10T03:52:20.407Z
Jimmy Song
<p>Bitcoin Core doesn't use an oldest-first selection but a more complex solver, it will probably end up spending outputs you don't want to in this particular case. You can do manual selection of the outputs you want to spend using the Coin Control section of the advanced GUI, which will let you ignore the dust if you don't want to spend it. </p>

<p><a href="https://i.sstatic.net/yUXEX.png" rel="noreferrer"><img src="https://i.sstatic.net/yUXEX.png" alt="Bitcoin Core Output Selection"></a></p>

CC BY-SA 3.0
2017-10-21T12:02:43.847Z
I'm new to bitcoin, but the question is about which inputs will be spent, so I think you have to change the 'outputs' with 'inputs', or is it interchangeable in this context?
croraf
CC BY-SA 3.0
2017-10-22T08:44:10.597Z
They’re two words for the same thing, inputs are outputs being spent.
Claris
CC BY-SA 3.0
2017-10-22T08:56:10.500Z
Inputs of the current transaction are some of the unspent outputs from previous transactions? In the picture the list is the list of unspent outputs, and checked ones will be used as inputs for current transaction?
croraf
CC BY-SA 3.0
2017-10-22T09:18:16.770Z
That is correct.
Claris
CC BY-SA 3.0
2015-11-10T05:16:34.410Z
2015-11-10T05:16:34.410Z
Claris
<p>Say someone holds 100,000 btc.  Over time, this address has been spammed with dust by numerous parties.  </p>

<p>Now, the oldest funds come from the previous large transaction.  If the dust is, say 0.0000101 btc, can someone send this exact amount elsewhere and get rid of the dust?  Or will the client get the oldest inputs and spend the dust from there?</p>

CC BY-SA 3.0
2015-11-10T03:57:35.043Z
Why the bitcoin-xt tag? AFAIK, coin selection is the same between XT/Core.
Nick ODell
CC BY-SA 3.0
2015-11-10T05:09:47.497Z
I figure some people might be looking at that tag specifically.
linhares
CC BY-SA 3.0
2015-11-10T11:18:24.060Z
possible duplicate of [What is the coin selection algorithm?](http://bitcoin.stackexchange.com/q/1077/5406), [How can I control which coins to spend in a transaction?](http://bitcoin.stackexchange.com/q/2527/5406), [What does Bitcoin Core's "Coin Control Features" do and how do I use it?](http://bitcoin.stackexchange.com/q/37486/5406)
Murch
CC BY-SA 4.0
2022-11-26T17:01:32.563Z
Does this answer your question? [What is the coin selection algorithm?](https://bitcoin.stackexchange.com/questions/1077/what-is-the-coin-selection-algorithm)
Geremia
<bitcoin-core><dust><coin-age-priority><coin-selection><coin-control>
Which inputs will be spent?
linhares
# Which inputs will be spent?

(Asked by: username_0 on 2015-11-10)

Say someone holds 100,000 btc. Over time, this address has been spammed with dust by numerous parties.

Now, the oldest funds come from the previous large transaction. If the dust is, say 0.0000101 btc, can someone send this exact amount elsewhere and get rid of the dust? Or will the client get the oldest inputs and spend the dust from there?

**Tags:** bitcoin-core, dust, coin-age-priority, coin-selection, coin-control

> **Comments:**
> **username_1**: Why the bitcoin-xt tag? AFAIK, coin selection is the same between XT/Core.  
> **username_0**: I figure some people might be looking at that tag specifically.  
> **username_2**: possible duplicate of [What is the coin selection algorithm?](http://bitcoin.stackexchange.com/q/1077/5406), [How can I control which coins to spend in a transaction?](http://bitcoin.stackexchange.com/q/2527/5406), [What does Bitcoin Core's "Coin Control Features" do and how do I use it?](http://bitcoin.stackexchange.com/q/37486/5406)  
> **username_3**: Does this answer your question? [What is the coin selection algorithm?](https://bitcoin.stackexchange.com/questions/1077/what-is-the-coin-selection-algorithm)  

---

## 2 answers

### Answer by username_6 on 2015-11-10. Score: 5 | Accepted answer

Bitcoin Core doesn't use an oldest-first selection but a more complex solver, it will probably end up spending outputs you don't want to in this particular case. You can do manual selection of the outputs you want to spend using the Coin Control section of the advanced GUI, which will let you ignore the dust if you don't want to spend it.

[![Bitcoin Core Output Selection](https://i.sstatic.net/yUXEX.png)](https://i.sstatic.net/yUXEX.png)

> **Comments:**
> **username_7**: I'm new to bitcoin, but the question is about which inputs will be spent, so I think you have to change the 'outputs' with 'inputs', or is it interchangeable in this context?  
> **username_6**: They’re two words for the same thing, inputs are outputs being spent.  
> **username_7**: Inputs of the current transaction are some of the unspent outputs from previous transactions? In the picture the list is the list of unspent outputs, and checked ones will be used as inputs for current transaction?  
> **username_6**: That is correct.  

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### Answer by username_4 on 2015-11-10. Score: 2

Depends on the software. You can construct a transaction that spends whichever utxos you want, so yes, you can send someone the exact amount of the sum of dust transactions. As for the transaction fee, the network may or may not relay, but even there, you may be able to get a friendly miner to mine it.

> **Comments:**
> **username_5**: The question seems to be specifically asking about the behavior of Bitcoin Core and/or XT.  

---

