About the Bitcoin Transaction Fee Calculator
A Bitcoin fee is the fee rate multiplied by the size of the transaction. This calculator works out the size in virtual bytes from the kind of address you spend from, the number of inputs and the number of outputs, then multiplies by the fee rate you type. You get the fee in satoshis and in BTC, and in money if you add a price. It supports legacy (1...), wrapped SegWit (3...), native SegWit (bc1q...) and Taproot (bc1p...) transactions, using their typical sizes. It is good for planning: how much will it cost to consolidate twenty small coins, how much cheaper is native SegWit than legacy, or what a payment costs at 5 or at 50 sat/vB. The tool works offline in your browser.
Updated October 2026
How to use the Bitcoin Transaction Fee Calculator
- 1Pick the address type you spend from.
- 2Enter the number of inputs (coins you spend) and outputs (payment, change and any extra payees).
- 3Enter a fee rate in sat/vB. The Bitcoin Fee Estimator shows the current rates.
- 4Optionally enter a price for one bitcoin to see the fee in money.
- 5Read the size in virtual bytes and the fee, then press Copy result.
The three numbers behind every fee
A fee has three parts: the size of the transaction, the fee rate, and the exchange rate if you want to see it in money. Size depends on the number of inputs and outputs and on the address type. The fee rate is what you offer to miners per virtual byte, and the market sets what works. The calculator keeps the first part exact, so you can try different fee rates quickly.
Consolidating coins is the classic use. Imagine twenty inputs and one output from native SegWit: that is about 1,400 virtual bytes, ten times the size of a normal payment. At 5 sat/vB it costs 7,000 sats, but at 50 sat/vB it costs 70,000. Waiting for a quiet moment saves real money.
Choosing the address type
- Native SegWit (bc1q) is the best default: small, widely supported, low fees.
- Taproot (bc1p) has the smallest inputs, but outputs are a bit larger, and some services cannot send to it yet.
- Wrapped SegWit (starting with 3) is cheaper than legacy but dearer than native SegWit.
- Legacy (starting with 1) is the largest. Move old funds to native SegWit when fees are low.
After you calculate
Look up the fee rate that fits your deadline in the Bitcoin Fee Estimator, then follow the payment with the Bitcoin Transaction Status Checker. Amounts in satoshis convert exactly with the Satoshi to BTC Converter, and the Bitcoin Address Validator tells you which type a receiving address is before you send.
Features
- Size from address type, inputs and outputs
- Legacy, wrapped SegWit, native SegWit and Taproot
- Fee in satoshis and BTC
- Fee in money from a price you type
- Shows weight units as well as virtual bytes
- Works offline in your browser
- Exact whole-satoshi rounding up, like wallets do
Frequently asked questions
How is a Bitcoin transaction fee calculated?
Fee = size in virtual bytes x fee rate in satoshis per virtual byte. The amount you send does not matter. A transaction with many inputs is bigger than one with a single input, so it costs more.
How big is a typical transaction?
A native SegWit payment with one input and two outputs is about 141 virtual bytes. The same payment from a legacy address is about 226. Taproot is around 154 for one input and two outputs.
Why does the size depend on the address type?
Each input must carry a signature and a public key or script. SegWit moves that data to a witness section that is counted at a discount, so SegWit inputs are cheaper than legacy inputs.
What is the difference between bytes, vBytes and weight units?
Weight units are the raw measure. A virtual byte is four weight units. Fees use virtual bytes. Legacy data counts four weight units per byte, witness data only one.
Is the result exact?
It is a close estimate for standard single-key transactions. Signatures vary by a byte, and multisig or scripted inputs are bigger. Your wallet shows the exact fee before you send.
How can I reduce the fee?
Use native SegWit or Taproot, send fewer inputs, choose a lower fee rate when you can wait, and avoid sending when the network is busy.
Does this send anything?
No. It is a calculator that runs entirely in your browser and never asks for an address or a key.