> For the complete documentation index, see [llms.txt](https://docs.fonbnk.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.fonbnk.com/server-to-server/servers.md).

# Servers

### API servers

| Environment | Base URL                                                          |
| ----------- | ----------------------------------------------------------------- |
| Sandbox     | [https://sandbox-api.fonbnk.com](https://sandbox-api.fonbnk.com/) |
| Production  | [https://api.fonbnk.com](https://api.fonbnk.com/)                 |

Sandbox and production are separate systems with separate credentials, separate users, and separate orders. Nothing crosses between them, so start in sandbox and move the same code to production by changing this base URL and your API keys.

Sandbox never moves real money. Its offers are simulated, and its quotes expose the extra `depositSandboxForcedFlow` and `payoutSandboxForcedFlow` fields so you can force an outcome on demand — a deposit success, invalid, underpayment or overpayment, and a payout success or failure. Which of those a given leg offers varies, so read the field's own `options` array. See [Create quote](/server-to-server/api-endpoints/create-quote.md) for how the fields arrive.

{% hint style="warning" %}
Sandbox contract addresses, bank names and carrier lists are fixtures. Never hard-code anything you read from a sandbox response — always take them from [Get available currencies](/server-to-server/api-endpoints/get-available-currencies.md) and from the quote.
{% endhint %}


---

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