Lightning Network
Payment channels, routing and invoices: Bitcoin payments in seconds.
The Lightning Network
Lightning is a network of payment channels on top of Bitcoin. Payments settle in seconds for tiny fees without a new on-chain transaction each time.
Payment channels
A Lightning payment channel is a 2-of-2 multisig output plus signed, unbroadcast transactions that record the latest balance. Learn how channels work.
Lightning routing
Lightning payments hop through a path of channels chosen by the sender, wrapped in onion layers so each hop sees only its neighbours. Learn how routing works.
HTLCs: hash time-locked contracts
An HTLC pays someone who reveals a secret before a deadline and otherwise refunds the sender. It makes multi-hop Lightning payments trustless. See how.
Lightning invoices
A Lightning invoice is a payment request with the amount, payment hash, expiry and routing hints. Learn how BOLT 11 invoices and BOLT 12 offers work.
Channel liquidity
On Lightning you can only send what's on your side of a channel and receive what's on the other side. Learn how to manage inbound and outbound liquidity.
Closing channels and watchtowers
Lightning channels close cooperatively or by force. Watchtowers watch the blockchain and punish cheating while you are offline. Learn how closing works.