Bitcoin fee calculator
Estimate the size of a Bitcoin transaction and what it costs to send at any fee rate, in satoshis, BTC and your own currency. Free, no sign-up, nothing leaves your browser.
A simple payment usually has one input and two outputs: the payment and your change. Sizes are typical figures for each address type, so the real size can differ by a byte or so. Enter today's fee rate and price from your wallet; the starting numbers are only an example.
| Fee rate | Sats | Cost (GBP) |
|---|---|---|
| 1 sat/vB | 141 | £0.07 |
| 5 sat/vB | 705 | £0.35 |
| 10 sat/vB | 1,410 | £0.71 |
| 20 sat/vB | 2,820 | £1.41 |
| 50 sat/vB | 7,050 | £3.53 |
Why some payments wait longer
Bitcoin adds a new block roughly every 10 minutes and each block has limited space. Miners choose which transactions to include, usually the ones paying the highest fee for their size. When many people send at once, the mempool fills up, fees rise and low-fee transactions can wait hours or longer.
If a payment gets stuck
Some wallets let you raise the fee on a waiting transaction, known as replace-by-fee, or send a follow-on transaction that pays a higher fee to pull both through. Very old unconfirmed transactions may eventually drop out of most mempools.
Launch your own crypto app
SendPay platforms let customers buy, sell and hold crypto, held with regulated partners, alongside GBP, EUR and USD accounts, powered by licensed partners. SendPay doesn't offer trading tools, DeFi or lending.