Can you have a transaction without a change output? While reading about the fees here https://metamug.com/article/security/bitcoin-transaction-fee-satoshi-per-byte.html
The article said that &quot;In the simplest case, you'll have one input and two outputs (the recipient, and change). So in=1 and out=2.&quot;
Does that mean that I cannot send the entire amount from one address to another? I thought that the simplest case is in=1 and out=1. And that in = out + fee
Yes, absolutely you can. I think the article intend &quot;the simplest case&quot; in the real world usage, where is highly unlikely that you have to pay the exact amount of one of your UTXO, if not they are wrong and your example is the simplest transaction you can made.