<p>You cannot say for sure.
The three options are potentially true.</p>
<p>However, many clients build transactions with the change output as the last output.
So, following this convention, I would say option 2 is the most likely.</p>

CC BY-SA 4.0
2020-07-02T10:07:34.100Z
In addition, the change output is most likely the output with the highest number of decimal digits.
MCCCS
CC BY-SA 4.0
2020-07-02T12:43:43.173Z
Most modern clients randomize the change output index now. Really nice ones like Bitcoin Core will also match the change address to be of the same address type as the payment address
Raghav Sood
CC BY-SA 4.0
2020-07-02T09:48:16.050Z
2020-07-02T09:48:16.050Z
FedFranz
<p>As a third party to the transaction, its hard to say what the most likely case is. You can guess, but there are a number of possibilities, and some wallet software will deliberately create transactions which confuse this sort of analysis.</p>
<p>To add to your list of possibilities:</p>
<ol>
<li>Someone sent 25.99 bitcoin to another person/organization</li>
<li>Someone sent 1 bitcoin to another person/organization</li>
<li>Someone sent 26.99 bitcoin to another person/organization</li>
<li>Someone sent 26.99 bitcoin to themselves</li>
<li>Someone sent 25.99 bitcoin to some person/organization, and 1 bitcoin to some different person/organization</li>
</ol>
<p>Some other more obscure(?) possibilities. These would perhaps be more probable if OP's post involved P2SH or P2MS addresses.</p>
<ol start="6">
<li>Two people shared ownership of the input, and each one of them now owns one of the outputs.</li>
<li>Numbers 1-5 again, but with 2+ people owning the input.</li>
<li>Numbers 1-7 again, but with 2+ people owning (each?) output.</li>
</ol>

CC BY-SA 4.0
2020-07-03T06:20:18.487Z
2020-07-03T06:20:18.487Z
chytrik
<p>I'm very new to this.
It’s hard to know for sure, but what’s most likely the case with the below transaction:</p>
<p><a href="https://i.sstatic.net/RZJNJ.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/RZJNJ.png" alt="enter image description here" /></a></p>
<ol>
<li>Someone sent 25.99 bitcoin to another person/organization</li>
<li>Someone sent 1 bitcoin to another person/organization</li>
<li>Someone sent 26.99 bitcoin to another person/organization</li>
</ol>

<bitcoin-core><blockchain>
Blockchain transaction change output
caketestico
# Blockchain transaction change output

(Asked by: username_0 on 2020-07-02)

I'm very new to this.
It’s hard to know for sure, but what’s most likely the case with the below transaction:

[![enter image description here](https://i.sstatic.net/RZJNJ.png)](https://i.sstatic.net/RZJNJ.png)

1. Someone sent 25.99 bitcoin to another person/organization
2. Someone sent 1 bitcoin to another person/organization
3. Someone sent 26.99 bitcoin to another person/organization

**Tags:** bitcoin-core, blockchain


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## 2 answers

### Answer by username_1 on 2020-07-02. Score: 2 | Accepted answer

You cannot say for sure.
The three options are potentially true.

However, many clients build transactions with the change output as the last output.
So, following this convention, I would say option 2 is the most likely.

> **Comments:**
> **username_2**: In addition, the change output is most likely the output with the highest number of decimal digits.  
> **username_3**: Most modern clients randomize the change output index now. Really nice ones like Bitcoin Core will also match the change address to be of the same address type as the payment address  

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### Answer by username_4 on 2020-07-03. Score: 1

As a third party to the transaction, its hard to say what the most likely case is. You can guess, but there are a number of possibilities, and some wallet software will deliberately create transactions which confuse this sort of analysis.

To add to your list of possibilities:

1. Someone sent 25.99 bitcoin to another person/organization
2. Someone sent 1 bitcoin to another person/organization
3. Someone sent 26.99 bitcoin to another person/organization
4. Someone sent 26.99 bitcoin to themselves
5. Someone sent 25.99 bitcoin to some person/organization, and 1 bitcoin to some different person/organization

Some other more obscure(?) possibilities. These would perhaps be more probable if OP's post involved P2SH or P2MS addresses.

6. Two people shared ownership of the input, and each one of them now owns one of the outputs.
7. Numbers 1-5 again, but with 2+ people owning the input.
8. Numbers 1-7 again, but with 2+ people owning (each?) output.


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