# Satoshis and Bitcoin units

1 bitcoin = 100,000,000 satoshis. Learn the units BTC, mBTC, bits and sats, convert between them exactly, and see why software counts in sats.

Canonical page: https://mybitcoinexplorer.com/learn/satoshis-and-bitcoin-units
Topic: Bitcoin basics
Published: 2026-10-29
Updated: 2026-10-30


## The smallest piece
A **satoshi** (or "sat") is the smallest amount Bitcoin can record: 0.00000001 BTC. One bitcoin is exactly 100,000,000 satoshis.

> Diagram: The common Bitcoin units, from largest to smallest — 

## Why software counts in sats
Inside Bitcoin, every amount is stored as a whole number of satoshis. There are no decimals at all. Wallets just divide by 100,000,000 to show you BTC.

That matters for developers: adding decimal numbers on a computer can create tiny rounding errors, so good software (including the MyBitcoinExplorer API) always works in whole sats.

> Interactive exercise: [open the lesson](https://mybitcoinexplorer.com/learn/satoshis-and-bitcoin-units).

## Everyday examples
| Amount | In sats |
|---|---|
| 1 BTC | 100,000,000 |
| 0.01 BTC | 1,000,000 |
| 0.0005 BTC | 50,000 |
| A typical fee of 1,000 sats | 0.00001 BTC |

> Fee rates are measured in **sats per virtual byte** (sat/vB). See [Fee rate: sats per vbyte](https://mybitcoinexplorer.com/learn/fee-rate-sat-per-vbyte).


## Why "sats" became popular
As the price of one bitcoin rose, everyday amounts became long decimals like 0.00012345 BTC. Saying "12,345 sats" is easier, and it is the number Bitcoin actually stores. Many wallets now let you show balances in sats by default.

## Quick conversions to remember
- 0.1 BTC = 10,000,000 sats
- 0.001 BTC = 100,000 sats
- 0.00001 BTC = 1,000 sats

## Where you'll see each unit
| Unit | Typical use |
|---|---|
| BTC | Prices, large balances |
| sats | Everyday payments, Lightning, fees |
| sat/vB | [Fee rates](https://mybitcoinexplorer.com/learn/fee-rate-sat-per-vbyte) |
| msat (millisatoshi) | Inside the [The Lightning Network](https://mybitcoinexplorer.com/learn/lightning-network) only |

Every amount on MyBitcoinExplorer, including the [API](/developers), is an exact whole number of sats behind the scenes.


## Key takeaways

- 1 BTC = 100,000,000 satoshis.
- Bitcoin stores every amount as a whole number of sats.
- Fee rates are quoted in sats per virtual byte.

## Common questions

### Why is it called a satoshi?

The unit is named after Bitcoin's creator, Satoshi Nakamoto.

### Can you send less than one satoshi?

Not on the blockchain. The Lightning Network can track millisatoshis internally, but on-chain amounts are whole sats.

### How many satoshis are in 1 bitcoin?

Exactly 100,000,000.

### Is a bit the same as a satoshi?

No. One bit (µBTC) is 100 satoshis.

## Related lessons

- [Why there will only be 21 million bitcoin](https://mybitcoinexplorer.com/learn/bitcoin-supply-21-million)
- [Fee rate: sats per vbyte](https://mybitcoinexplorer.com/learn/fee-rate-sat-per-vbyte)
- [Transaction outputs](https://mybitcoinexplorer.com/learn/transaction-outputs)
- [What is Bitcoin?](https://mybitcoinexplorer.com/learn/what-is-bitcoin)