> ## Documentation Index
> Fetch the complete documentation index at: https://second.tech/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# Swaptopia

> Swap bitcoin between on-chain and Lightning with Swaptopia, a self-custodial wallet app that runs in your browser and needs no account.

Swaptopia lives at [labs.second.tech/swaptopia](https://labs.second.tech/swaptopia/).

<Note>
  Swaptopia is in beta and opens on mainnet, where a swap moves real bitcoin. Swap only amounts you can afford to lose, or [test a swap on signet](/docs/swaptopia/wallet#test-a-swap-on-signet) first with test bitcoin.
</Note>

<Frame caption="The quote shows what your Lightning wallet app receives after the swap's fees, before you select Swap">
  <img src="https://mintcdn.com/second-0659a37d/Ys6dqcbJ8GNgbFCj/images/swaptopia/swap-bitcoin-to-lightning.png?fit=max&auto=format&n=Ys6dqcbJ8GNgbFCj&q=85&s=beec28350f18363941815187e3970930" alt="Screenshot of the Swaptopia swap card, with 50,000 sats and the Bitcoin label in You send, the estimated Lightning amount and its fee lines in You receive, and the Swap button" width="1152" height="1122" data-path="images/swaptopia/swap-bitcoin-to-lightning.png" />
</Frame>

## What Swaptopia handles for you

* **A wallet of your own:** Swaptopia creates a wallet in your browser the first time you open the page, and signs every swap with its keys.
* **Bitcoin to Lightning:** Swaptopia [boards](/docs/learn/board) the bitcoin you send onto Ark, then pays the Lightning invoice or Lightning address you give it.
* **Lightning to bitcoin:** Swaptopia receives your Lightning payment, then [offboards](/docs/learn/offboard) the sats to the on-chain address you paste.

## Before your first swap

* [Back up your seed phrase](/docs/swaptopia/backup). Swaptopia shows it only until you confirm the backup. Nobody can recover your sats without it.
* Keep the tab open during the stages that ask for it. If you lose the tab, [reopen the same page in the same browser](/docs/swaptopia/troubleshooting#resume-a-swap-after-closing-the-tab) to carry on with the swap.
* Check the [amount limits](/docs/swaptopia/fees-and-limits#amount-limits). On mainnet, a bitcoin-to-Lightning swap starts at 51,000 sats or more.

## Set up and use Swaptopia

<CardGroup cols={2}>
  <Card title="Back up your wallet" icon="key" href="/docs/swaptopia/backup">
    Write down the seed phrase before your first swap, and export the wallet data if you run the Bark CLI.
  </Card>

  <Card title="Swap bitcoin to Lightning" icon="bolt" href="/docs/swaptopia/bitcoin-to-lightning">
    Send bitcoin to the address Swaptopia gives you, then paste a Lightning invoice.
  </Card>

  <Card title="Swap Lightning to bitcoin" icon="bitcoin-sign" href="/docs/swaptopia/lightning-to-bitcoin">
    Pay a Lightning invoice and receive an on-chain transaction to your address.
  </Card>

  <Card title="Fees and limits" icon="receipt" href="/docs/swaptopia/fees-and-limits">
    Read the quote, and check the minimums and maximums for each direction.
  </Card>

  <Card title="Manage your wallet" icon="wallet" href="/docs/swaptopia/wallet">
    Send leftover sats, restore or wipe the wallet, and export its data.
  </Card>

  <Card title="Resolve a swap problem" icon="life-ring" href="/docs/swaptopia/troubleshooting">
    Find the message you see on screen and what to do about it.
  </Card>
</CardGroup>


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