Bitcoin · Calculator

Bitcoin transaction fees,
calculated from first principles.

Estimate your transaction fee. Enter your UTXOUnspent Transaction Output (UTXO)A piece of bitcoin you received and have not yet spent, like a separate bill in a wallet. Your balance is the total of your UTXOs. Spending uses up whole UTXOs and creates new ones, usually including change sent back to you, and each UTXO carries its own history, which matters for privacy.Full definition count, address type, and current fee rate. See the fee in sats, BTCBitcoin (BTC)The ticker symbol for Bitcoin, used on exchanges and in price quotes.Full definition, and USD. SegWit and Taproot are compared side by side so you can see the savings.

The question it answersHow much will my Bitcoin transaction fee cost in sats and dollars?

Privacy: runs in your browser. What you enter stays on your device unless you copy a share link, which puts your inputs in the link.

Most sends: 2 (recipient + change).

BTC price as of 2026-09-19 snapshot. Edit to update.

Byte sizes are standard single-signature estimates for each script type (BIP 141 for SegWit, BIP 341 for Taproot).

YOUR TRANSACTION
SIZE
0 vB
FEE (SATS)
0
FEE (BTC)
0
FEE (USD)
$0
COMPARED ACROSS ADDRESS TYPES
Type Size (vB) Fee (sats) Fee (USD)
TIP

SegWit addresses (bc1q...) cost roughly 40% less than Legacy addresses (1...) for the same transaction. Taproot (bc1p...) runs about 10% larger than SegWit for a standard 1-input, 2-output send because its outputs are bigger, and pulls ahead once a 2-output send spends 3 or more UTXOs.

What this tool assumes
  • Fee rates are in satoshis per vByte; typical transaction size assumes 1-input/2-output SegWit.
  • Network congestion can spike fees dramatically; mempoolmempoolThe waiting area for Bitcoin transactions that have been broadcast to the network but not yet confirmed in a block.Full definition.space shows live rates.
Where the vbytes go: 1 input, 2 outputs
Legacy226.0 vB
148 vB68 vBWhole SegWit send, 140.5 vB
SegWit140.5 vB
68 vB62 vB
Taproot154.0 vB
57.5 vB86 vB
0226.0 vB
The input: one per UTXO spentTwo outputs (recipient + change) in the row's address typeAbout 10 vB of fixed overhead
Fee = size × fee rate, so at any one fee rate a shorter bar is a smaller fee. Each extra UTXO adds one more orange segment of the same size (148, 68 or 57.5 vB); the outputs and overhead stay the same.
The tool's default send, drawn to scale. One Legacy input (148 vB) is bigger than the whole SegWit send (140.5 vB). Legacy falls further behind with every UTXO added. Taproot has the smallest input but bigger outputs, so it trails SegWit here and gains with each extra UTXO spent.

Estimates only. Actual wallet fees depend on script details. Verify live rates at mempool.space.

HOW THIS IS CALCULATED

This tool runs entirely in your browser: no data is sent to any server. Size = overhead + inputs × input size + outputs × output size; fee = size × fee rate, converted to USD at the BTC price entered. Verify the methodology or inspect the source code in your browser's dev tools.

Where to go from here

Read next

Mempool, Fees & RBF/CPFP

mempool.space, fee estimation, virtual bytes, RBF, and CPFP.

Explore further
  • Sparrow Wallet GuideSparrow Wallet setup with hardware wallets, your own node via Tor, UTXO labeling and coin control, PSBT workflow, and air-gapped Coldcard signing in detail.
  • UTXO Consolidation AnalyzerCompares the fee cost of consolidating UTXOs now versus spending them individually later under different fee-rate assumptions.
  • Lightning vs On-Chain CostCompares Lightning and on-chain transaction fees for a given payment amount and current fee environment.

Sources

Verify badges in the text link to these sources. Figures, rates and rules change: check each source’s date before acting on it.

  1. mempool.space, mempool.space fee estimates ↩

Calculators are educational estimates, not financial advice. Disclosures · How pages are reviewed