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Make Bitcoin.now preferred → Opens Google’s source preferences. You stay in control.A Bitcoin miner fee is transaction virtual size multiplied by the selected sat/vB rate. The bitcoin amount does not set the fee, and no public estimate can guarantee a confirmation time.
One node’s view of valid unconfirmed transactions. Other nodes may see a slightly different set.
Each bar shows how much transaction data is waiting in a fee-rate band. Roughly 1,000,000 vB fits in one block, though real blocks vary.
Loading public mempool data…
Fee estimates are probabilistic and never guarantee a confirmation time.
These are arithmetic examples, not current recommendations.
Each Bitcoin node keeps its own collection of valid, unconfirmed transactions. That collection is called a mempool. Nodes receive transactions at different times and can use different memory limits, so there is no single perfectly identical global mempool.
Block space is limited. Miners normally select transactions that offer more fee revenue for their virtual size, which is why fee rate matters more than total fee when transactions compete.
First decide how quickly the payment really needs to confirm. Then inspect current public estimates and let a maintained wallet calculate the exact transaction size. When demand is high, waiting can be cheaper. For an urgent payment, check whether the wallet supports replace-by-fee before broadcasting.
A public estimate describes recent conditions, not a guarantee. A new group of transactions can enter the mempool seconds later, while a block can clear demand sooner than expected.
A fee rate is measured in satoshis per virtual byte. Total fee is transaction size multiplied by that rate. A larger transaction can pay a larger total while using the same rate. Spending many small unspent transaction outputs usually creates a larger transaction than spending one UTXO. The wallet can sometimes consolidate inputs when fees are low, but consolidation is itself an on-chain transaction and can affect privacy.
Replace-by-fee, or RBF, lets a sender replace an eligible unconfirmed transaction with one that pays a higher fee. Child-pays-for-parent, or CPFP, spends an unconfirmed output with a high enough child fee to make the combined package attractive. Support depends on transaction details, node policy, and wallet software.
Batching pays several recipients in one transaction and can reduce the size per payment. It is common for services making many withdrawals. It can also reveal that outputs are related, so efficiency and privacy are not the same question.
No. A payment of 0.01 BTC can cost more or less than a payment of 1 BTC. Transaction structure, virtual size, and fee rate drive the miner fee.
Not always. An exchange or custodian can set a customer withdrawal charge that differs from the actual miner fee in its batched transaction.
RBF or CPFP may help when the transaction and wallet support them. Check the wallet’s documentation before taking action.
A good fee choice begins with the transaction’s virtual size and real deadline. The highest public estimate is not automatically the right answer for every payment.
Transactions compete by fee rate, not by the amount of bitcoin sent. New demand and newly mined blocks can change the queue quickly.
A maintained wallet estimates exact size and may support fee bumping. RBF and CPFP have different requirements and cannot rescue every transaction.
| Situation | First check | Possible response | Important limit |
|---|---|---|---|
| Not urgent | Low-priority fee bands | Wait for lower demand | Demand may rise instead |
| Urgent and unsent | Wallet size and current estimates | Choose a suitable higher rate | No estimate guarantees a block |
| Unconfirmed with RBF | Replacement eligibility | Increase the fee rate | Replacement rules apply |
| Service withdrawal | Provider’s fee policy | Compare total withdrawal cost | Charge may exceed miner fee |