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

# Bridge tokens across chains using ProofBridge transfers

> Step-by-step guide to making a cross-chain transfer as a Bridger: browse liquidity ads, deposit funds, and receive destination tokens via ZK proof.

Bridging tokens on ProofBridge means transferring assets from one blockchain to another through a peer-to-peer match with a liquidity provider (Maker). You deposit your source-chain tokens into the OrderPortal contract, the Maker locks their destination-chain tokens against your order, and a zero-knowledge proof settles both sides trustlessly. The entire process typically completes within a few minutes.

<Note>
  ProofBridge currently operates on testnet (Ethereum Sepolia and Stellar Testnet). Use testnet funds only. You need two kinds of testnet funds:

  1. **Gas** — Sepolia ETH from a public faucet, Stellar Testnet XLM from [friendbot](https://friendbot.stellar.org/).
  2. **Bridge tokens** — the ERC-20 / SAC / SEP-41 tokens you'll actually send. Claim them from the in-app [Faucet](https://app.pfbridge.xyz/faucet) after connecting your wallet; it lists every bridgeable token on each supported chain.
</Note>

## Prerequisites

* A connected and authenticated wallet on the source chain. See [Connect your wallet](/guides/connect-wallet).
* Sufficient gas on the source chain to cover the transaction.
* Testnet tokens to bridge — claim them from the in-app [Faucet](https://app.pfbridge.xyz/faucet) if you don't already hold any.

## Bridge your tokens

<Steps>
  <Step title="Connect your wallet on the source chain">
    Open [ProofBridge](https://app.pfbridge.xyz) and connect your wallet to the source chain (the network where you currently hold tokens). If you are not yet connected, follow the [connect wallet guide](/guides/connect-wallet).

    Make sure your wallet is set to the correct network — for example, Ethereum Sepolia if you are sending ETH.
  </Step>

  <Step title="Browse the liquidity marketplace">
    Navigate to the **Marketplace** tab. The app fetches available liquidity ads from the relayer (`GET /v1/ads`). Each ad shows:

    * Source chain and destination chain
    * Token pair (for example, ETH → XLM)
    * Available liquidity amount
    * Maker's offered rate
    * A **bot icon** next to the maker's address when the ad is served by ProofBridge's auto-merchant

    Use the filters to narrow results by source chain, destination chain, or token symbol.

    <Tip>
      Ads marked with a bot icon are operated by ProofBridge's auto-merchant — orders against them are picked up and locked automatically, so they typically settle faster than manually-monitored ads.
    </Tip>
  </Step>

  <Step title="Select an ad that matches your route">
    Click an ad that matches the chain pair and token pair you want. Review the details — including the available amount and any rate information — then click **Select** or **Use this ad**.

    <Tip>
      Choose an ad with sufficient liquidity to cover your intended transfer amount. If an ad does not have enough available balance, it will not appear as selectable for your amount.
    </Tip>
  </Step>

  <Step title="Enter the transfer amount and recipient address">
    In the order form, enter:

    * **Amount**: How many tokens you want to send from the source chain.
    * **Recipient address**: The wallet address on the destination chain that should receive the tokens.

    <Note>
      If you are sending native ETH or XLM, it is automatically wrapped to WETH or WXLM on deposit. You do not need to wrap tokens manually before bridging.
    </Note>
  </Step>

  <Step title="Request pre-authorization">
    Click **Request authorization**. In the background, the frontend calls `POST /v1/trades/create` on the relayer. The relayer validates the route, checks the ad has sufficient liquidity, and returns pre-authorized transaction parameters.

    This step does not submit anything on-chain yet. Wait for the authorization confirmation to appear — it takes a few seconds.
  </Step>

  <Step title="Sign and submit the deposit transaction">
    Once authorized, click **Confirm and deposit**. Your wallet opens a transaction prompt showing the OrderPortal contract address and the deposit amount. Review the details and click **Confirm** in your wallet.

    This transaction deposits your source-chain tokens into the OrderPortal smart contract and records the order hash in the on-chain Merkle Mountain Range.

    <Warning>
      Only approve this transaction after reviewing the contract address and amount carefully. Once submitted, the deposit is locked until the ZK proof settles both sides.
    </Warning>
  </Step>

  <Step title="Confirm the transaction to the relayer">
    After the deposit transaction is confirmed on-chain, click **Notify relayer** (or the app does this automatically). This triggers the relayer callback (`POST /v1/trades/:id/confirm`), which tells the relayer to verify the transaction and begin proof generation.

    <Note>
      The relayer operates on a pre-authorization model — it does not monitor chain events automatically. Your callback is what prompts it to proceed. If you close the app before confirming, you can return and complete this step from the [order tracking page](/guides/track-orders).
    </Note>
  </Step>

  <Step title="Wait for ZK proof generation and settlement">
    The relayer fetches the Merkle inclusion proof for your order from both chains, then triggers the Noir proof circuit to generate a zero-knowledge proof. This typically takes **1–3 minutes**.

    Once the proof is ready, the relayer submits it to both chains:

    1. **AdManager** on the destination chain releases the Maker's tokens to your recipient address.
    2. **OrderPortal** on the source chain releases your deposited tokens to the Maker's recipient address.

    Both settlements happen atomically — if one side fails, neither releases funds.
  </Step>

  <Step title="Receive your destination tokens">
    When settlement is complete, the destination-chain tokens arrive at the recipient address you specified. You can verify the transfer in your destination-chain wallet or block explorer.

    The order status in ProofBridge updates to **Completed**. See [Track orders](/guides/track-orders) to monitor status throughout the process.
  </Step>
</Steps>

## Estimated time

| Phase                            | Typical duration                |
| -------------------------------- | ------------------------------- |
| Pre-authorization                | \< 5 seconds                    |
| Deposit transaction confirmation | 15–60 seconds (chain-dependent) |
| ZK proof generation              | 1–3 minutes                     |
| Settlement on both chains        | 30–90 seconds                   |

Total end-to-end time is usually **3–5 minutes**.

## If your transfer is stuck

<AccordionGroup>
  <Accordion title="The order is still in 'created' status after several minutes">
    The relayer callback may not have been sent. Navigate to **My Orders**, find the order, and click **Notify relayer** to manually trigger the confirmation step.
  </Accordion>

  <Accordion title="The order is in 'locked' status for more than 10 minutes">
    Proof generation is in progress. This phase can occasionally take longer due to circuit computation. Wait a few more minutes, then check again. If the status does not change after 15 minutes, contact support.
  </Accordion>

  <Accordion title="The order failed or was rejected">
    If the pre-authorization check fails (for example, the ad's liquidity was taken by another Bridger between your selection and submission), the order is rejected before any on-chain transaction. Return to the marketplace and select a different ad. No funds are at risk.
  </Accordion>
</AccordionGroup>

<Tip>
  Keep the ProofBridge tab open until the order reaches **Completed** status. This ensures the relayer callback is sent automatically after your deposit confirms.
</Tip>