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

# Quickstart

> Set up your Sandbox API keys, create a funded account, and send a test transaction

**Base API URL:** `https://sandbox.cdp.coinbase.com`

## 1. Create Sandbox API keys

<Steps>
  <Step title="Access CDP Portal Sandbox">
    Navigate to Sandbox mode in the CDP Portal
  </Step>

  <Step title="Create Sandbox API key">
    * Go to **Settings**
    * Click **Create secret API Key**
    * Enter an **API key nickname**
    * **Download the API key JSON file** and save it securely
  </Step>
</Steps>

## 2. Install CDP CLI

[CDP CLI](/get-started/build-with-ai/cdp-for-agents) is a command-line tool that handles JWT authentication automatically — configure your API key once and it takes care of signing every request for you.

```bash theme={null}
npm install -g @coinbase/cdp-cli
cdp --version
```

<Info>
  Node.js 22 or later is required.
</Info>

**Configure your API key:**

```bash theme={null}
cdp env sandbox --key-file ~/Downloads/cdp_api_key.json
```

<Warning>
  Never commit API keys to version control. Store them securely in environment variables or a secrets manager. Do not use real personal data in the Sandbox environment.
</Warning>

## 3. Create and fund an account through the portal

<Steps>
  <Step title="Go to Sandbox Accounts">
    In Sandbox mode, navigate to the Accounts tab
  </Step>

  <Step title="Create test account">
    Name the account (e.g., "My Test Account")
  </Step>

  <Step title="Add test assets">
    Add balances in different assets to your account. Currently we support USD, USDC, USDT (e.g., set USD to \$1000)
  </Step>
</Steps>

<Frame>
  <img src="https://mintcdn.com/coinbase-prod/XmV3g17i7b8SBr0T/images/sandbox_account_balance.png?fit=max&auto=format&n=XmV3g17i7b8SBr0T&q=85&s=16c3bcc710959a8cfe1d357c267c9e10" alt="Sandbox account showing test balances for USD, USDT, and USDC" width="1116" height="660" data-path="images/sandbox_account_balance.png" />
</Frame>

<Warning>
  All balances are simulated within the Sandbox environment — no blockchain or testnet connectivity. You cannot fund accounts by sending real or testnet crypto.
</Warning>

## 4. Verify balance(s)

Run the following to verify your account balance:

```bash theme={null}
cdp accounts balance <accountId>
```

<Tip>
  List all your account IDs:

  ```bash theme={null}
  cdp accounts list
  ```
</Tip>

## 5. Alternative: Test with Postman

Prefer a GUI? See the [Postman guide](/get-started/sandbox/postman) for setup instructions.

## 6. Test custodial API flows

Now that you're set up, use these quickstarts to test the custodial APIs end to end in Sandbox:

<CardGroup cols={2}>
  <Card title="Custodial Wallets Quickstart" icon="wallet" href="/wallets/custodial-wallets/quickstart">
    Create an entity-owned account, add simulated balances through the Portal, and verify balances with the CDP CLI or SDK.
  </Card>

  <Card title="Customers Quickstart" icon="user-check" href="/customers-kyc/quickstart">
    Onboard a KYC'd customer, create customer-owned accounts, and test capability changes.
  </Card>

  <Card title="Payment Methods Quickstart" icon="credit-card" href="/payments/payment-methods/quickstart">
    List mock payment methods and test successful and failed fiat withdrawal flows.
  </Card>

  <Card title="Deposit Destinations Quickstart" icon="arrow-down-to-line" href="/payments/deposit-destinations/quickstart">
    Create a placeholder deposit address, simulate an incoming deposit, and inspect webhook payloads.
  </Card>

  <Card title="Transfers Quickstart" icon="arrow-right-arrow-left" href="/payments/transfers/quickstart">
    Send Sandbox transfers to reserved crypto addresses, test emails, and payment methods.
  </Card>

  <Card title="API Reference" icon="code" href="/api-reference/v2/introduction">
    Explore request and response schemas for Sandbox-compatible APIs.
  </Card>
</CardGroup>

## Sandbox test data and scenarios

Use the product quickstarts above for the full API walkthroughs. These Sandbox-specific fixtures are available when you test custodial API flows:

### Accounts

* Sandbox accounts are isolated from Live and do not require linking to external Coinbase accounts.
* Account funding is available through the Portal UI with simulated balances only. You cannot fund Sandbox accounts by sending real or testnet crypto.
* Supported test balances in the Portal include USD, USDC, and USDT.

### Payment methods

Sandbox automatically creates entity-level test payment methods based on your entity's region. Use active methods to test successful withdrawals and inactive methods to test error handling.

#### US entities

| Payment rail | Bank                   | Status     | Behavior          |
| ------------ | ---------------------- | ---------- | ----------------- |
| Fedwire      | JPMorgan Chase Bank NA | `active`   | Transfers succeed |
| Fedwire      | Bank of America NA     | `inactive` | Transfers fail    |
| Swift        | Deutsche Bank          | `active`   | Transfers succeed |

#### EU entities

| Payment rail | Bank                        | Status     | Behavior          |
| ------------ | --------------------------- | ---------- | ----------------- |
| SEPA         | Deutsche Bank               | `active`   | Transfers succeed |
| SEPA         | Baden-Wurttembergische Bank | `inactive` | Transfers fail    |

### Deposit destinations

* In Sandbox, deposit destinations are placeholder addresses for API testing. They are not real blockchain addresses and the Sandbox does not connect to any blockchain network.
* The API uses **deposit destination** for the resource. The Portal UI uses **deposit address** for the same concept.
* Deposit simulation uses the Sandbox-only `/fake/deposit/crypto` endpoint or the Portal **Deposit** action. The `asset_symbol` and `network` must match the destination configuration.
* Simulated deposits fire transfer webhooks, create transfer records visible through the Transfers API, and credit the account balance immediately.

<Warning>
  Do not send real funds to Sandbox deposit addresses. They do not exist on any blockchain and your funds will be lost.
</Warning>

### Transfers

Sandbox transfers are simulated. Webhooks fire and transfer statuses change, but no real crypto transaction or fiat rail movement occurs.

#### Reserved crypto addresses

| Reserved address                             | Simulated outcome       |
| -------------------------------------------- | ----------------------- |
| `0x1111111111111111111111111111111111111111` | Success                 |
| `0x2222222222222222222222222222222222222222` | Transfer invalid target |
| `0x3333333333333333333333333333333333333333` | Invalid address         |
| `0x4444444444444444444444444444444444444444` | Unsupported network     |

#### Reserved email addresses

| Test email                         | Simulated outcome                                                               |
| ---------------------------------- | ------------------------------------------------------------------------------- |
| `testuser1@domain.com`             | Successful validation and execution                                             |
| `testuser2@domain.com`             | Successful validation and execution                                             |
| `sandboxinvalidtarget@domain.com`  | Invalid email target                                                            |
| `sandboxexecutionfails@domain.com` | Validation succeeds, execution fails synchronously with `422`                   |
| `sandboxasyncfailure@domain.com`   | Execution starts, then transitions from `processing` to `failed` asynchronously |

Any other email returns a `4xx` error so Sandbox does not validate real email addresses.

## What to read next

For a GUI-based testing option, see [Testing with Postman](/get-started/sandbox/postman). For product-specific concepts, continue with these references:

<CardGroup cols={2}>
  <Card title="Payment APIs Overview" icon="book" href="/payments/overview">
    Learn how accounts, payment methods, deposit destinations, and transfers fit together.
  </Card>

  <Card title="Custodial wallets" icon="wallet" href="/wallets/custodial-wallets/overview">
    Use accounts, balances, and transfers with your custodial funds.
  </Card>
</CardGroup>

## Transitioning to Live

When you're ready to move from Sandbox to Live:

* **Complete integration testing**: Ensure all features work correctly in Sandbox
* **Create Live API keys**: Generate Live credentials in the CDP Portal
* **Update configuration**: Switch from `sandbox.cdp.coinbase.com` to `api.cdp.coinbase.com`
* **Start with small transactions**: Begin with small test transactions to verify everything works
* **Set up monitoring**: Configure alerting for failed transactions and API errors