> For the complete documentation index, see [llms.txt](https://docs.lightning.engineering/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.lightning.engineering/lightning-network-tools/loop.md).

# Loop

[Lightning Loop](https://lightning.engineering/posts/2020-02-05-loop-beta/) is a service that allows users to make a Lightning transaction to an onchain Bitcoin address (Loop Out), or send on-chain Bitcoin directly into a Lightning channel (Loop In). Loop can help manage channel liquidity, for example, by emptying out a channel and [acquiring inbound capacity](/the-lightning-network/liquidity/how-to-get-inbound-capacity-on-the-lightning-network.md) (or refilling a depleted channel).

Lightning Loop uses submarine swaps to transact non-custodially, meaning that Loop is trustless. Loop Out transactions are batched to save on transaction fees.

Loop uses [L402s](/the-lightning-network/l402/l402.md) for authentication.

{% content-ref url="/pages/-MdQmlMeL52UXRy8DQ7G" %}
[Get Started](/lightning-network-tools/loop/get-started.md)
{% endcontent-ref %}

{% content-ref url="/pages/-MdQng4ie9\_aCJTcRhjH" %}
[The Loop CLI](/lightning-network-tools/loop/the-loop-cli.md)
{% endcontent-ref %}

{% content-ref url="/pages/-MVqm3k55X9JBo897t4F" %}
[Autoloop](/lightning-network-tools/loop/autoloop.md)
{% endcontent-ref %}

{% content-ref url="/pages/VFyeg7YaWX4NPRgBreAU" %}
[Static Loop In Addresses](/lightning-network-tools/loop/static-loop-in-addresses.md)
{% endcontent-ref %}

{% content-ref url="/pages/280rxpospNMmp2L6TTHi" %}
[Instant Loop Outs](/lightning-network-tools/loop/instant-loop-outs.md)
{% endcontent-ref %}

{% content-ref url="/pages/JQN3L6RH0M3bFluqvlLl" %}
[Peer with Loop](/lightning-network-tools/loop/peer-with-loop.md)
{% endcontent-ref %}

{% embed url="<https://lightning.engineering/api-docs/api/loop/>" %}


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