# Units

Units of Bitcoin most commonly are expressed in decimal exponents such as BTC (“bitcoins”), mBTC (“millibitcoins”) and μBTC (“bits”).

## Description

Bitcoin Explained Episode 8: Units of Bitcoin

Bitcoin has a metric system of denominations used as units of Bitcoin. The main goal of the bitcoin currency, abbreviated BTC, is to make it harmonious to worldwide currencies. Bitcoin tries to accomplish this function by being divisible down to the 8 decimal place. This is an adequate thing, given the actual high price of 1 Bitcoin theses days. The smallest denomination in a Bitcoin is called ‘Satoshi’, in homage to its creator. Below is a list of the named denominations and their value in BTC[1].

### Decimal metric units

The BTC unit was chosen to represent a value of 108 so as to give sub-unit precision rather than large whole numbers. Mirroring the standard Le Système International d’Unités, this allows for divisions of 1/10th (deci-bitcoins, dBTC), 1/100th (centi-bitcoins, cBTC), 1/1 000th (milli-bitcoins, mBTC), and 1/1 000 000 (micro-bitcoins, μBTC).

### Bits

The term “bit” is a popular new unit being used to represent smaller Bitcoin amounts. Due to the rising value of 1 bitcoin (currently 1 BTC = \$450 USD), many prices must be displayed in fractional bitcoin amounts. For example, a bottle of beer might be priced at .0085 BTC. These fractional numeric values can be confusing and difficult for many people to read. The bit sub-unit (equal to 0.000001 BTC) is considered by many to be a more memorable and intuitive way of displaying Bitcoin amounts; the aforementioned beer would cost 8500 bits.

Originally proposed on Bitcoin the sub-reddit, and now being embraced by the payment processor Bitpay, the bit sub-unit offers the following advantages:

• More compatible with existing financial software that can only handle 2 decimal places. For example: using a figures like 49.99 bits instead of .00004999 bitcoins.
• Figures would remain easily readable in the event of an extreme rise in Bitcoin’s exchange rate: if 1 Bitcoin was worth \$100,000, then a \$4.99 beer would cost 49.90 bits.
• Bit is an easier to remember unit when compared to other longer unit names and acronyms: 100 bits instead of 100 microbitcoins/100 μBTC/1 millibitcoin/1 mBTC).

However, there are some disadvantages to the bits nomenclature:

• Can be confused with the binary unit “bit” in computing, or the old-fashioned US currency unit of “bit”, which is 12.5 cents.
• Unit prefix terms such as micro-, milli-, and centi- are more familiar to those who use the metric measurement system (i.e. everyone except Americans)[2].

### Table of all units

This table is intended to include all well-defined units of bitcoin value, including less common and niche units.

Unit Abbreviation Decimal (BTC) Alternate names Info
Algorithmic maximum 20,999,999.9769     Calculation
tam-bitcoin 2,814,749.76710656 1,0000,0000 tonal
mega-bitcoin MBTC 1,000,000          Rare in context
kilo-bitcoin kBTC 1,000          Rare in context
hecto-bitcoin hBTC 100          Rare[3]
Initial block subsidy 50          Until block 210000
bong-bitcoin ᵇTBC 42.94967296 1,0000 tonal
Current block subsidy 12.5        block As of block 420000
deca-bitcoin daBTC 10          Rare
mill-bitcoin ᵐTBC 2.68435456 1000 tonal
bitcoin BTC 1          coin SI base unit
san-bitcoin ˢTBC 0.16777216 100 tonal
deci-bitcoin dBTC 0.1        Rare
ton-bitcoin ᵗTBC 0.01048576 10 tonal
centi-bitcoin cBTC 0.01       bitcent Formerly frequent Bitcents were frequent until the November 2013 bubble
milli-bitcoin mBTC 0.001      millibit, millie Occasional
bitcoin TBC 0.00065536 Tonal base unit
bitcoin-ton TBCᵗ 0.00004096 0.1 tonal
bitcoin-san TBCˢ 0.00000256 0.01 tonal
micro-bitcoin μBTC 0.000001   bit Frequent
bitcoin-mill TBCᵐ 0.00000016 0.001 tonal
0.0000001  finney[4]
bitcoin-bong TBCᵇ 0.00000001 0.0001 tonal
sat 0.00000001 Satoshi Blockchain value
msat 0.00000000001 millisatoshi[5] Payment channel value