Bitcoin Transactions and UTXOs

Cryptography, the UTXO model, chain types, scaling, and tokenomics.

Updated 2026 ж. 21 қаз.GaiaEx Academy Editorial

Бұл сабақта

Bitcoin's UTXO accounting model
How it differs from account balances

Негізгі тұжырымдар

1Your balance is the sum of unspent outputs (UTXOs)
2Each spend consumes UTXOs and creates new ones
3Ethereum instead tracks account balances directly

Сабақ қорытындысы

Bitcoin tracks ownership through UTXOs, or unspent transaction outputs.

Mental model

Bitcoin Transactions and UTXOs in plain terms

Bitcoin tracks ownership through UTXOs, or unspent transaction outputs. Instead of one account balance changing, coins are represented as chunks that are consumed and recreated.

Bitcoin's UTXO accounting model
How it differs from account balances

Mechanics

How to reason about Bitcoin transactions and UTXOs

A transaction spends existing UTXOs and creates new UTXOs.

Wallet balance is the sum of spendable outputs controlled by the wallet.

Ethereum-style account models update account balances directly.

Your balance is the sum of unspent outputs (UTXOs)
Each spend consumes UTXOs and creates new ones
Ethereum instead tracks account balances directly

Example

Bitcoin Transactions and UTXOs in practice

If you control one 1 BTC UTXO and send 0.3 BTC, the transaction can create 0.3 BTC for the recipient and about 0.7 BTC back to your change address, minus fees.

Есте сақтаңызDecision rule: When fees are high, remember that the number and size of UTXOs can matter as much as the payment amount.

Common mistakes

The usual Bitcoin transactions and UTXOs trap

Users may think a Bitcoin wallet has one simple balance on-chain. Under the hood, wallet software selects UTXOs to fund each spend.

Risk notes

What can go wrong with Bitcoin transactions and UTXOs

Poor UTXO management can increase fees, reduce privacy, or create dust that is expensive to spend.

Define UTXO.
Explain change output.
Compare UTXO with account balance models.

Practice

Make Bitcoin transactions and UTXOs stick

Define UTXO.
Explain change output.
Compare UTXO with account balance models.

Қайталау

Негізгі терминдер

Address: A public identifier (a string of characters) where crypto can be sent on a blockchain. Safe to share — it does not expose your private key.
Bitcoin (BTC): The first cryptocurrency, launched in 2009 — a decentralized, hard-capped (21M) digital money.
Blockchain: A shared, append-only ledger replicated across many computers, secured by cryptography and consensus.
Ethereum (ETH): A programmable blockchain — a 'world computer' that runs smart contracts and dApps.
Tokenomics: The economic design of a token — its supply, demand, incentives, and distribution.

Дерек көздері