Satoshi

Beginner
A satoshi is the smallest unit of a bitcoin. It equals one-hundred-millionth of a bitcoin or 0.00000001 BTC. As such, one bitcoin equals 100 million satoshi. The satoshi was named as an homage to the anonymous creator or creators behind Bitcoin, Satoshi Nakamoto. The satoshi is often abbreviated as sat.

1 satoshi = 0.00000001 BTC

It’s necessary for a currency to be able to be divided into smaller subdivisions if it aims to act as a global medium of exchange. Fiat currencies can be divided into smaller denominations, such as the penny for the British pound or the cent for the US dollar. Bitcoin, as a digital currency, can also be divided into smaller denominations.
As defined by the Bitcoin protocol, a single bitcoin can’t be divided further than 1 satoshi. All amounts on the blockchain are denominated in satoshi but are typically converted to bitcoin by most platforms. However, when considering small fractions of a bitcoin, many platforms will display the value in satoshi for easy readability.
Although the satoshi is the smallest unit a single bitcoin can be divided into, some scenarios may require further division of a satoshi. Payment channels, for example, a scalability solution for Bitcoin, may sometimes be denominated in millisatoshi, amounting to one hundred billionths of a single bitcoin. In theory, if needed, the Bitcoin protocol could be updated in the future to allow for further subdivision of a bitcoin.

Traditionally, the plural of satoshi has also been satoshi; however, satoshis is also correct and widely used. As of yet, no currency symbol has been widely adopted for the satoshi.

Other units of denomination of a bitcoin also exist. Most of them are used very scarcely, but some commonly used ones are:

  • 1 millibitcoin (mBTC) equals one-thousandth of a bitcoin, or 0.001 BTC.
  • 1 microbitcoin (μBTC) equals one-millionth of a bitcoin, or 0.000001 BTC.