What is a satoshi (sats)?

Do you need a whole bitcoin to use it? No, just as you don’t need a whole euro to count a price in cents. The difference is the scale: bitcoin is divided into far more pieces. Their name comes from Satoshi Nakamoto, the pseudonym of Bitcoin’s creator or group of creators.

If your wallet shows 0.0005 BTC, you have 50,000 sats. If you send 10,000 sats, you’re sending 0.0001 BTC. The asset doesn’t change, only the unit of measurement. It’s like writing the same distance in meters instead of kilometers. Many wallets let you choose which of the two units you see.

Why it matters

Sats make small amounts easier to read. Instead of counting zeros after the decimal point, you see a whole number. For us, that’s their main everyday benefit: less confusion when reading a balance or typing in a payment.

You’ll come across them often on the Lightning Network, a payment network built on top of Bitcoin that makes small, fast transfers easier. Transaction fees on the base network are also often shown in sat/vB, i.e. satoshis per virtual byte. The virtual byte is a unit that measures a transaction’s size for calculating the fee. This figure is a fee rate, not the total cost of the transfer.

What to watch out for

Before you confirm a transfer, check whether the amount field uses BTC or sats. The same digits in a different unit can mean a completely different amount. Also check the total fee: a small transfer on the base network can cost disproportionately much when the network is congested.

Finally, sats aren’t a separate cryptocurrency and don’t have a price independent of bitcoin. Their ratio to BTC stays fixed, but their value in euros moves with the price of bitcoin. More sats on screen don’t, by themselves, mean more purchasing power.