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

# Stablecoin FX

> Build real-time, onchain stablecoin FX products with transparent pricing, instant settlement, and predictable fees on Arc.

Build onchain stablecoin FX and swap products on Arc. With native multi-currency
support, [sub-second settlement](/arc/concepts/deterministic-finality), and
composable crosschain liquidity with [App Kits](/app-kit), Arc gives you the
infrastructure for transparent, low-cost currency exchange.

For direct wallet-to-wallet transfers, see [P2P Payments](/build/payments). For
merchant checkout flows, see [eCommerce Checkout](/build/ecommerce).

## Sample apps

Production-ready examples on GitHub you can fork and customize.

<Columns cols={2}>
  <Card title="Arc fintech" icon="building-columns" href="https://github.com/circlefin/arc-fintech">
    Multichain treasury system with crosschain capital movement using Circle
    Developer-Controlled Wallets, Gateway, and Bridge Kit.
  </Card>

  <Card title="Arc multichain wallet" icon="wallet" href="https://github.com/circlefin/arc-multichain-wallet">
    Unified USDC balance and crosschain transfers using Circle Gateway, Next.js,
    and Supabase.
  </Card>
</Columns>

## Quickstarts

Get up and running with FX and swap flows in minutes.

<Columns cols={2}>
  <Card title="Swap tokens" icon="arrows-rotate" href="/app-kit/quickstarts/swap-tokens-same-chain">
    **Beginner**. Exchange one token for another on the same blockchain using
    the [Swap](/app-kit/swap) capability.
  </Card>

  <Card title="Swap tokens crosschain" icon="globe" href="/app-kit/quickstarts/swap-tokens-crosschain">
    **Intermediate**. Combine [bridging](/app-kit/bridge) and
    [swapping](/app-kit/swap) to exchange tokens across blockchains.
  </Card>

  <Card title="Bridge tokens across blockchains" icon="bridge" href="/app-kit/quickstarts/bridge-tokens-across-blockchains">
    **Beginner**. Transfer USDC between blockchains using [App
    Kit](/app-kit/bridge).
  </Card>

  <Card title="Deposit and spend a Unified Balance" icon="coins" href="/app-kit/quickstarts/unified-balance-deposit-and-spend">
    **Intermediate**. Combine USDC from multiple blockchains into a single,
    instantly spendable balance.
  </Card>
</Columns>

## Why Arc for stablecoin FX

Arc is purpose-built for stablecoin finance. These capabilities directly support
FX and swap applications.

<AccordionGroup>
  <Accordion title="Real-time settlement">
    [Deterministic finality](/arc/concepts/deterministic-finality) — the
    guarantee that a confirmed transaction cannot be reversed or reorganized —
    settles FX trades in under a second, giving counterparties immediate
    certainty.
  </Accordion>

  <Accordion title="Transparent pricing">
    Onchain swap rates with configurable slippage tolerance give users full
    visibility into execution price. See [set slippage
    tolerance](/app-kit/tutorials/swap/set-slippage-tolerance-or-stop-limit).
  </Accordion>

  <Accordion title="Multi-stablecoin pairs">
    Swap between USDC, EURC, and other supported stablecoins natively on Arc.
    See [contract addresses](/arc/references/contract-addresses) for available
    tokens and [swap fees](/app-kit/concepts/swap-fees) for pricing details.
  </Accordion>

  <Accordion title="Predictable fees">
    Stable USDC-denominated [gas fees](/arc/references/gas-and-fees) remove fee
    volatility from FX calculations, so you can quote accurate rates.
  </Accordion>

  <Accordion title="Crosschain liquidity">
    App Kits [bridges](/app-kit/bridge) and [swaps](/app-kit/swap) compose
    across chains for multi-leg FX routing without custom infrastructure.
  </Accordion>

  <Accordion title="Fee monetization">
    Collect a custom spread fee on every swap without writing new smart
    contracts. See [collect swap fee](/app-kit/tutorials/swap/collect-swap-fee).
  </Accordion>
</AccordionGroup>