The units of bitcoin
One bitcoin divides into 100 million satoshis, named after the pseudonymous creator of the protocol. Because the base unit is so large, most everyday amounts are more naturally expressed in sats.
BTC = sats ÷ 100,000,000
USD = sats ÷ 100,000,000 × BTC price
| Unit | In satoshis | In BTC |
|---|---|---|
| satoshi | 1 | 0.00000001 |
| microbitcoin (bit) | 100 | 0.000001 |
| millibitcoin (mBTC) | 100,000 | 0.001 |
| centibitcoin (cBTC) | 1,000,000 | 0.01 |
| bitcoin | 100,000,000 | 1 |
A worked example
250,000 sats with bitcoin at $68,000:
| In BTC | 0.00250000 |
|---|---|
| In dollars | $170.00 |
| Sats per dollar | 1,470 |
Why people count in sats
- Readability. "50,000 sats" is easier to hold in your head than "0.0005 BTC", and much harder to misread by a decimal place.
- Fewer costly mistakes. Sending 0.005 instead of 0.0005 is a ten-fold error that a whole-number format makes obvious.
- Lightning payments. Small transfers on the Lightning Network are denominated in sats as a matter of course, and fees are often a single-digit number of them.
- Psychology. Owning 500,000 of something feels different from owning 0.005 of something, even though they are identical. Whether that helps or hurts is up to you.
Sats per dollar as a price gauge
Some people track how many sats a dollar buys rather than the dollar price of a coin. The figure moves inversely to the price, so a falling number means bitcoin is getting more expensive. It is a useful frame for anyone accumulating on a schedule — see the DCA calculator for modelling that directly.
Common questions
How many satoshis are in one bitcoin?
Exactly 100,000,000. Bitcoin is divisible to eight decimal places and the satoshi is the smallest of them.
How much is one satoshi worth?
Divide the bitcoin price by 100 million. At $68,000 per BTC, a single satoshi is worth about $0.00068.
How do I convert sats to dollars?
Divide the sats by 100 million to get BTC, then multiply by the current bitcoin price.
What is a millibitcoin?
One thousandth of a bitcoin, or 100,000 satoshis. It sits between the satoshi and the whole coin as a mid-sized unit.
Can I buy a fraction of a bitcoin?
Yes. Every exchange sells fractions, and most people who own bitcoin own less than a whole one.