Satoshi to Bitcoin Converter

One bitcoin is 100 million satoshis

Bitcoin is divisible to eight decimal places, and the smallest unit is the satoshi, named after the pseudonymous creator. There is no smaller unit on-chain: every amount in the protocol is an integer number of satoshis, and the decimal bitcoin figure is a display convention layered on top. This is deliberate — integer arithmetic avoids the floating-point rounding errors that would be catastrophic in a ledger.

The unit ladder

1 BTC is 1,000 mBTC (millibitcoin), 1,000,000 bits (microbitcoin), or 100,000,000 satoshis. So 1 mBTC is 100,000 sats and 1 bit is 100 sats. The bit was promoted for a while as a friendlier retail unit; sats won in practice, largely because Lightning Network fees and small payments are naturally expressed in them.

Why the eight-decimal display causes errors

0.00021 BTC and 0.0021 BTC differ by a factor of ten and look nearly identical at a glance. Bitcoin transactions are irreversible, so a misread decimal is a permanent loss. Working in satoshis removes the problem entirely: 21,000 sats and 210,000 sats are not visually confusable. This is the practical argument for sat-denominated interfaces, and why most exchanges and wallets now offer the display option.

Fees are quoted in sats per vbyte

Transaction fees are not a percentage. They are paid per unit of block space consumed, measured in virtual bytes, so a fee is quoted as sats/vB and the total cost depends on transaction size, not value transferred. A typical simple transaction is around 140 vB, so at 20 sats/vB it costs roughly 2,800 sats regardless of whether it moves 0.001 BTC or 100 BTC.

Dust and the unspendable balance

An output too small to be worth spending — where the fee to move it exceeds its value — is called dust, and nodes refuse to relay outputs below a threshold, commonly 546 sats for standard outputs. A wallet balance can therefore include amounts that are economically unspendable at current fee rates, which is why the spendable figure sometimes differs from the total.

Twenty-one million, not twenty-one million bitcoin of supply

The cap is 21 million BTC, which is 2.1 quadrillion satoshis. Expressed that way it is clearer that divisibility, not the headline cap, determines whether the unit is usable at scale.