# Optional parameters

| Parameter  | Value                                                                                                                                                                                                                                                                                                              | Description                                                                                                                                                                             |
| ---------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| bsc        | *fiat codes*                                                                                                                                                                                                                                                                                                       | The payment fiat currency that you want to show the payer by default.                                                                                                                   |
| curs       | *fiat codes*                                                                                                                                                                                                                                                                                                       | List of authorized fiat currencies (leave empty for all)                                                                                                                                |
| crys       | *crypto codes*                                                                                                                                                                                                                                                                                                     | List of authorized cryptocurrencies (leave empty for all)                                                                                                                               |
| net        | <p>arbitrum\_mainnet avalanche\_mainnet</p><p>base\_mainnet</p><p>bitcoin\_mainnet</p><p>bsc\_mainnet</p><p>celo\_mainnet</p><p>lightning\_mainnet</p><p>mainnet</p><p>matic\_mainnet optimism\_mainnet</p><p>rsk\_mainnet</p><p>sonic\_mainnet</p><p>tezos\_mainnet</p><p>xdai\_mainnet</p><p>zksync\_mainnet</p> | Default network                                                                                                                                                                         |
| nets       | <p>arbitrum\_mainnet avalanche\_mainnet</p><p>base\_mainnet</p><p>bitcoin\_mainnet</p><p>bsc\_mainnet</p><p>celo\_mainnet</p><p>lightning\_mainnet</p><p>mainnet</p><p>matic\_mainnet optimism\_mainnet</p><p>rsk\_mainnet</p><p>sonic\_mainnet</p><p>tezos\_mainnet</p><p>xdai\_mainnet</p><p>zksync\_mainnet</p> | List of authorized networks (leave empty for all).                                                                                                                                      |
| lang       | <p>en                                                                                                                                                                                                                                                                                                              |                                                                                                                                                                                         |
| <br>fr     |                                                                                                                                                                                                                                                                                                                    |                                                                                                                                                                                         |
| <br>de     |                                                                                                                                                                                                                                                                                                                    |                                                                                                                                                                                         |
| <br>it     |                                                                                                                                                                                                                                                                                                                    |                                                                                                                                                                                         |
| <br>es     |                                                                                                                                                                                                                                                                                                                    |                                                                                                                                                                                         |
| <br>pt</p> | Display language                                                                                                                                                                                                                                                                                                   |                                                                                                                                                                                         |
| mode       | dark                                                                                                                                                                                                                                                                                                               | If used, switches the UI theme to dark mode.                                                                                                                                            |
| phone      | integer                                                                                                                                                                                                                                                                                                            | Pre-fills the user's mobile phone number during the login step. Enter it as numbers that begin with the country code. Example : phone=41791234567 for the phone number +41 79 123 45 67 |
| ctry       | <p>ISO alpha-2 country code: <br>CH</p><p>FR</p><p>DE</p><p>...</p>                                                                                                                                                                                                                                                | Sets the default country code displayed at the phone number input step. If not used, the country code is automatically selected based on the user's detected timezone.                  |
| mylogo     | logo URL                                                                                                                                                                                                                                                                                                           | Add your own logo, which will be displayed in the widget's footer left of the "powered by Mt Pelerin".                                                                                  |
| primary    | XXXXXX                                                                                                                                                                                                                                                                                                             | Primary color, where XXXXXX is the color's hexadecimal code, for example: %23F7931A                                                                                                     |
| success    | XXXXXX                                                                                                                                                                                                                                                                                                             | CTA color, where XXXXXX is the color's hexadecimal code, for example: %23F7931A                                                                                                         |

**Fiat codes:** AUD, CAD, CHF, CZK, DKK, EUR, GBP, HKD, HUF, JPY, MXN, NOK, NZD, PLN, SEK, SGD, USD, ZAR

**Crypto codes:** AVAX, BNB, BTC, BTC.b, BTCB, cbBTC, CELO, crvUSD, DAI, ETH, EURA, EURC, EURS, FRAX, GHO, LUSD, PAXG, POL, RBTC, RIF, S, sat, tzBTC, USDC, USDC.e, USDRIF, USDT, WBTC, WETH, XAUt, XDAI, XTZ, ZCHF

{% hint style="info" %}
To add multiple values for a given parameter, simply separate them with a comma.
{% endhint %}

{% hint style="warning" %}
**All parameters must be URL encoded.**

**Example:**

\#FFFFFF

**must be passed as**

%23FFFFFF
{% endhint %}


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