Spark

A Bitcoin layer-two network for instant, low-fee transfers.

Spark is a Bitcoin layer-two — a network built on top of Bitcoin that settles back to the main chain but lets you transact instantly and cheaply. You hold your own keys, and transfers between Spark users are effectively instant with very low fees.

It sits alongside Lightning and on-chain in a self-custody wallet: Spark for fast everyday transfers, Lightning for instant payments to anyone on the Lightning Network, and on-chain for the base layer.

BTCBitByBit's wallet uses Spark (via the Breez SDK) so your family can send and receive Bitcoin quickly without thinking about which network they're on — you just hold your keys and use it.

Learn this in our courses

Course topic

Wallets & self-custody

How to store Bitcoin so that nobody — not even us — can take it.

Related terms

Glossary

Lightning Network

A second-layer Bitcoin payment network that enables instant, low-fee transactions.

Glossary

Liquid Network

A Bitcoin sidechain built for fast, low-fee transactions and asset issuance.

Glossary

Sats

Short for satoshis — the smallest unit of Bitcoin. 100 million sats = 1 BTC.

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