I would be surprised if the SAT were divisible on L1... is it? I would be surprised if the SAT were not divisible on L2...is it? If the SAT is divisible anywhere, then to what decimal place?

Is the SAT truly atomic?

1 Answer 1


The native unit of the Bitcoin protocol is the satoshi. All output values in Bitcoin transactions are expressed in whole numbers of satoshis. Bitcoin's protocol does not use any non-integer values for consensus relevant data. Therefore, the atomic unit of value in the Bitcoin protocol is the satoshi.

The Lightning Network uses millisatoshi (1 sat = 1000 msat) for all values pertaining to channel updates: e.g. channel balances, HTLC amounts, forwarding fees, and invoice amounts. Since millisatoshis cannot be expressed in Bitcoin transactions, the respective amounts are rounded down to whole satoshis in the outputs of commitment transactions or when closing a channel. Any remaining split satoshis are dropped to fees.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.