Transactions and confirmations
Crypto Dispensers | Bitcoin learning path
AI-generated narration. Original diagrams; fictional examples.
Reviewed October 23, 2026.

Separate the payment systems
Maya wants to understand a Bitcoin payment before sending one. She first identifies the asset, the supported network and the receiving instructions. A familiar ticker alone doesn't answer all three questions. An on-chain Bitcoin address is different from a Lightning payment request, and a token on another network has different rules. Don't choose a network only because its displayed fee is lower. Both sides must support the exact transfer you're considering.

A wallet spends earlier outputs
An output assigns an amount under particular spending conditions. Until it is spent, it is called an unspent transaction output, or UTXO. A wallet's balance can be the total of several such amounts. To send, the wallet selects earlier outputs as inputs and creates new outputs. It signs using the required keys. The coins aren't files being copied out of the phone. This structure helps explain change, fees and why a transaction can pay more than one destination.

Work through the amounts
Use the same fictional payment as stage two. Maya spends an input of one hundred thousand sats, assigns thirty thousand to Leo and sixty-nine thousand back to herself as change. The difference, one thousand sats, is the network fee. The fee isn't an extra output paid to Leo. The recipient doesn't receive the whole input. When reading a transaction, match the intended destination to its output rather than treating every output as your receipt. All these amounts are invented arithmetic.

Fee rate and total fee differ
A virtual byte is a unit used to measure a transaction's weight for fee calculations. Suppose a fictional transaction is two hundred and fifty virtual bytes and uses a rate of four sats per virtual byte. Its total network fee is one thousand sats. Sending more dollars' worth of Bitcoin doesn't by itself determine that size. Inputs, outputs and their types matter. Network fees, a provider's purchase charges and a bank's charges are different costs. An example isn't a live estimate or a promised confirmation time.

Broadcast is not a confirmation
Broadcast means a signed transaction has been shared with other computers. Some nodes may hold it in their local collection of unconfirmed transactions, called a mempool. There isn't one universal waiting list seen identically by everyone. Inclusion in a block on the current chain gives the first confirmation. Later blocks add confirmations. A receiving service may require a particular count and other account checks before crediting an available balance. Broadcast, confirmation and account credit are different events.

Count blocks without promising a clock
In this fictional example, a transaction is included at block height nine hundred thousand. When the chain tip is nine hundred thousand and two, it has three confirmations: the block containing it, plus two later blocks. The count is the current tip minus the inclusion height, plus one, while that block remains on the accepted chain. Bitcoin targets about ten minutes between blocks on average. It doesn't promise the next block, or your transaction's inclusion, at an exact time.

Why history can change
Competing valid blocks can temporarily create different branches. Nodes follow the valid chain with the most accumulated proof of work. If another branch wins, a recent transaction's confirmation count can change, and the payment may become unconfirmed or conflict with another spend. More confirmations generally reduce reversal risk. They don't establish the recipient's honesty or turn the wrong destination into the right one. Network assurance and checking the purpose of a payment remain separate tasks.

Find out who can change a fee
Some wallets support replacing an unconfirmed transaction with a higher-fee version. Other techniques depend on spendable outputs, policy and control. These are conditional tools, not a universal button that cancels or guarantees a payment. If a provider prepared the withdrawal, ask that provider about its options. Don't pay an unfamiliar accelerator promising certainty or share keys to speed things up. Confirm which transaction and step are pending before attempting any change.

Provider waiting and network waiting
A bank payment, account review or withdrawal request can be pending before any on-chain transaction exists. A public explorer can't show a private provider review. A bank receipt can't prove that Bitcoin was broadcast. Describe the exact status and record you have. Ask whether funding arrived, whether the purchase completed and whether a transfer was broadcast. Sending the same payment again doesn't diagnose the delay and can create a second transaction.

Try explaining zero confirmations
Maya sees a genuine Bitcoin transaction with zero confirmations. Does that show that her bank never sent dollars, that the recipient already credited her account, or only that it isn't included in a block on the current chain? Only the last conclusion follows from zero confirmations. Return to stage five for its example and check. Try the fee arithmetic and confirmation count in your own words. Neither calculation promises a completion deadline.

Continue: https://www.cryptodispensers.com/learn#lp-transactions

Sources and further reading
https://developer.bitcoin.org/devguide/transactions.html
https://developer.bitcoin.org/devguide/block_chain.html
https://bitcoin.org/en/you-need-to-know