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UTXO

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What Is A UTXO?

What Is A Bitcoin UTXO?

UTXO is short for unspent transaction output and is any particular fraction of a bitcoin that has not been spent. A single UTXO can hold any amount of bitcoin such as a fraction of a bitcoin or multiple bitcoin. UTXOs can be combined or split into multiple UTXOs to generate payments of any size.

In a standard bitcoin transaction, each input is an existing UTXO being destroyed and each output is a new UTXO being generated.

UTXO Set

Every full bitcoin node maintains a list of all of the existing UTXOs in existence known as the UTXO set. This set is updated anytime a block of transactions generates or destroys unspent transaction outputs. This allows nodes to verify a transaction’s authenticity as well as the bitcoin it is attempting to spend. Since each and every transaction is audited by the nodes, every UTXO can be traced back to when it was created as part of a block reward.

A Fraction Of A Bitcoin

You can think of your unspent transaction outputs as bitcoin that you haven’t spent yet. When you spend a UTXO, that particular fraction of a bitcoin gets spent and becomes a new UTXO at the receiving address. When that address spends it, it becomes the unspent bitcoin of another address and so on… This cycle continues forever as bitcoin circulates globally. Owning a fraction of a bitcoin is actually owning 1 or more unspent transaction outputs.

By design, it’s not possible to spend the same UTXO twice because they are processed continuously and are part of the beginning and end of each transaction. When a transaction is completed, any unspent outputs are recorded on the blockchain and will be used later as the inputs in a new transaction. The concept of an Unspent transaction output can be difficult to grasp at first, but after sending a few transactions and looking them up on a block explorer, it begins to make more sense.

UTX Hoes

UTX Hoes is bitcoin slang derived from the term “unspent transaction output”, is used to describe individuals, often women, who engage in romantic relationships solely for the purpose of accessing the bitcoin holdings of their partner.

While this has been known to work on weak-handed simps and shitcoiners, it doesn’t get in the way of the strong-handed hodlers who are thinking long term.

UTXO FAQ

Learning all about inputs and outputs can take some time but hopefully these frequently asked questions can help you understand things more clearly.

What Does UTXO Stand For?

UTXO stands for unspent transaction output and it is a fraction of a bitcoin that has not yet been spent.

Why Do You Have To Use All Of A UTXO?

A UTXO is like a physical coin – you can’t just use part of it, you have to use the whole thing. Why is that? Well, each unspent output represents a specific amount of Bitcoin that was previously received in a transaction, and the only way to “spend” that Bitcoin is to use the entire UTXO as the input for a new transaction. It’s kind of like if someone gave you a dollar bill – you wouldn’t be able to spend just 50 cents of it, you’d have to use the whole dollar. This concept is often referred to as “full send”, meaning that you send the entire amount of Bitcoin in the UTXO to the new recipient. It might seem a little confusing at first, but understanding how wallets manage your balance is essential to properly using Bitcoin.