# On-Off Ramp

## Supported Stablecoins

<table><thead><tr><th>Stablecoin</th><th width="107.74072265625">Network</th><th>Ramp type</th><th>Network fee*</th></tr></thead><tbody><tr><td><strong>CUSD / USDC / USDT</strong></td><td>CELO</td><td>On-ramp &#x26; Off-ramp</td><td>$0.01</td></tr><tr><td><strong>USDC</strong></td><td>BSC</td><td>Onramp &#x26; Off-ramp</td><td>0.03</td></tr><tr><td><strong>USDC</strong></td><td>OP</td><td>On-ramp &#x26; Off-ramp</td><td>$0.03</td></tr><tr><td><strong>USDC</strong></td><td>BASE</td><td>On-ramp &#x26; Off-ramp</td><td>$0.03</td></tr><tr><td><strong>USDC</strong></td><td>MATIC</td><td>On-ramp &#x26; Off-ramp</td><td>$0.03</td></tr></tbody></table>

\* Network fees are deducted from the customer’s payout.

***

## Getting Started

All you need is a **public API key**.\
Create one by following the [authentication guide](/cashramp/introduction/authentication.md).

The ramp is delivered as a URL you build with query parameters.

### Base URLs

<table><thead><tr><th width="160.6666259765625">Environment</th><th>URL</th></tr></thead><tbody><tr><td><strong>Staging</strong></td><td><code>https://staging.useaccrue.com/hosted/ramp</code></td></tr><tr><td><strong>Production</strong></td><td><code>https://useaccrue.com/hosted/ramp</code></td></tr></tbody></table>

### URL Parameters

<table><thead><tr><th width="176.77777099609375">Name</th><th width="93.8887939453125">Required</th><th>Description</th></tr></thead><tbody><tr><td><code>key</code></td><td><strong>Yes</strong></td><td>Your public API key.</td></tr><tr><td><code>paymentType</code></td><td><strong>Yes</strong></td><td><code>deposit</code> or <code>withdrawal</code>.</td></tr><tr><td><code>address</code></td><td>No</td><td>Wallet to receive funds. If omitted, Cashramp tries <code>window.ethereum</code>.</td></tr><tr><td><code>coin</code></td><td><strong>Yes</strong></td><td>Stablecoin symbol (see table above).</td></tr><tr><td><code>network</code></td><td><strong>Yes</strong></td><td>Network name from the table.</td></tr><tr><td><code>amount</code></td><td>No</td><td>Quantity of the stablecoin.</td></tr><tr><td><code>reference</code></td><td>No</td><td>Your idempotent reference.</td></tr><tr><td><code>redirectUrl</code></td><td>No</td><td>Where to send the user after completion.</td></tr><tr><td><code>currency</code></td><td>No</td><td>ISO-4217 fiat code (e.g., <code>USD</code>).</td></tr><tr><td><code>phone</code></td><td>No</td><td>Customer’s phone number.</td></tr><tr><td><code>hideAddress</code></td><td>No</td><td><code>true</code> to hide the wallet address field.</td></tr><tr><td><code>isWalletContext</code></td><td>No</td><td>Set <code>false</code> to ignore <code>window.ethereum</code> and use your own flow. Default <code>true</code>.</td></tr></tbody></table>

{% code title="Example" overflow="wrap" %}

```url
https://useaccrue.com/hosted/ramp?key=CSHRMP-PUBK_mO86nN3ye84hIso&paymentType=deposit&coin=CUSD&network=CELO&amount=10&reference=test_reference
```

{% endcode %}

***

## Custom Crypto-Deposit Flow

When `window.ethereum` is present, Cashramp prompts the user to sign the transfer automatically.\
If it isn’t, we emit a `postMessage` so you can run your own UX:

```javascript
window.addEventListener("message", (event) => {
  if (event.origin === "https://useaccrue.com") {
    const { event: name, payload } = event.data;
    if (name === "crypto.requested") {
      const amountUsd = Number(payload.amountCents) / 100;
      const destination = payload.destinationAddress;
      const paymentRequestId = payload.paymentRequest;

      /*
       * Launch your custom flow to send EXACTLY
       * `amountUsd` worth of stablecoins to `destination`.
       * After broadcasting, call confirmTransaction (below).
       */
    }
  }
});
```

***

## Confirm Transaction

After broadcasting the transfer, poll `confirmTransaction` until it settles.\
Poll in line with block times: CELO & Optimism ≈ 10 s; Ethereum ≈ 60 s.

{% code overflow="wrap" %}

```graphql
mutation {
  confirmTransaction(
    paymentRequest: "VHlwZXM6OkNhc2hyYW1wOjpBUEk6Ok1lcmN6YW50UGF5bWVudFJlcXVlc3QtZjVkZDdhYWEtZDI1Yy00YTZmLTkwODMtNzk1NjdkOTNjNmM4"
    transactionHash: "0x4321897b3c4495a314d081dbcf2cb5310b19834bda124f5ad03e07464b1add73"
  )
}
```

{% endcode %}

<table><thead><tr><th width="187.33331298828125">Argument</th><th>Description</th></tr></thead><tbody><tr><td><code>paymentRequest</code></td><td>Global ID from the earlier <code>crypto.requested</code> payload.</td></tr><tr><td><code>transactionHash</code></td><td>Hash of your on-chain transfer.</td></tr></tbody></table>

### What Happens Next

* The payment request moves from `pending_funding` → `created`.
* A webhook fires with the updated status.
* Cashramp emails the user a link to withdraw the fiat equivalent.

***


---

# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://docs.cashramp.co/cashramp/onchain-ramp/on-off-ramp.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.