# On-ramp Widget Customization
The FaTPay widget could be customized by passing query parameters. The following parameters empower our partners to tailor the user experience according to their businesses.
{% hint style="info" %}
All keys and values of parameters are case-sensitive. All values' format is **String**.
{% endhint %}
## **Parameters f**or all pages
### `language`
* ***Description:*** Language code chosen from \[[languages](https://dev.fatpay.org/appendix/languages "mention")] for FaTPay widget, e.g. *`language=en`*;
* ***Default:*** en;
* ***Scope:*** Applicable for all partners;
* ***Required:*** Optional for all partners;
* ***Signed:*** Not required to sign;
## **Parameters f**or quotation page
### `fiatCurrency`
* ***Description:*** Fiat currency codes chosen from \[[fiat-currencies](https://dev.fatpay.org/appendix/fiat-currencies "mention")] for FaTPay widget to provide a list of selected fiat currencies to the user. Multiple currency codes should be concatenated with comma as separator, e.g. *`fiatCurrency=USD,THB`*. Then user can only pay in `USD` or `THB`;
* ***Default:*** All available fiat currencies;
* ***Scope:*** Applicable for all partners;
* ***Required:*** Optional for all partners;
* ***Signed:*** Not required to sign;
### `defaultFiatCurrency`
* ***Description:*** Fiat currency code chosen from \[[fiat-currencies](https://dev.fatpay.org/appendix/fiat-currencies "mention")] for FaTPay widget to display default fiat currency to the user, e.g. *`defaultFiatCurrency=USD`*. Then USD is selected as default fiat currency;
* ***Default:*** USD. If fiatCurrency is set, then it's the first fiat currency code;
* ***Scope:*** Applicable for all partners;
* ***Required:*** Optional for all partners;
* ***Signed:*** Not required to sign;
### `amount`
* ***Description:*** Default fiat currency amount with two decimal digits max, e.g. *`amount=100.45`*.
* ***Default:*** None;
* ***Scope:*** Applicable for all partners;
* ***Required:*** Optional for all partners;
* ***Signed:*** Not required to sign;
### `amountFixed`
* ***Description:*** Fixed fiat currency amount with two decimal digits max which can't be modified by the user, e.g. *`amountFixed=100`*.
* ***Default:*** None;
* ***Scope:*** Applicable for all partners;
* ***Required:*** Optional for all partners;
* ***Signed:*** Not required to sign;
### `cryptoCurrency`
* ***Description:*** Cryptocurrency codes chosen from \[[cryptocurrencies-on-ramp](https://dev.fatpay.org/appendix/cryptocurrencies-on-ramp "mention")] for FaTPay widget to provide a list of selected Cryptocurrency to the user. Multiple currency codes should be concatenated with comma as separator, e.g. *`cryptoCurrency=USDT_ERC20,USDT_POLYGON`*. Then user can only buy `USDT_ERC20` or `USDT_POLYGON`;
* ***Default:*** All available cryptocurrencies;
* ***Scope:*** Applicable for all partners;
* ***Required:*** Optional for all partners;
* ***Signed:*** Not required to sign;
### `defaultCurrency`
* ***Description:*** Cryptocurrency code chosen from \[[cryptocurrencies-on-ramp](https://dev.fatpay.org/appendix/cryptocurrencies-on-ramp "mention")] for FaTPay widget to display default cryptocurrency to the user, e.g. *`defaultCurrency=USDT_POLYGON`*. Then `USDT_POLYGON` is selected as default cryptocurrency;
* ***Default:*** If *`cryptoCurrency`* is set, the default value is the first cryptocurrency code. Otherwise, it's `USDT_ERC20`;
* ***Scope:*** Applicable for all partners;
* ***Required:*** Optional for all partners;
* ***Signed:*** Not required to sign;
### `cryptoNetwork`
* ***Description:*** Cryptocurrency network chosen from \[[cryptocurrencies-on-ramp](https://dev.fatpay.org/appendix/cryptocurrencies-on-ramp "mention")] for FaTPay widget to provide a list of selected Cryptocurrency on certain public blockchains to the user, e.g. *`cryptoNetwork=POLYGON,ETHEREUM`*. Then the user can only buy the cryptocurrencies on `POLYGON` and `ETHEREUM`;
* ***Default:*** All available crypto networks;
* ***Scope:*** Applicable for all partners;
* ***Required:*** Optional for all partners;
* ***Signed:*** Not required to sign;
## **Parameters f**or wallet address page
### `walletAddress`
* ***Description:*** Default wallet address which could be modified by the user. FaTPay will validate the wallet address if it's match with the chosen cryptocurrency. The wallet address filed will be left empty if the validation is failed. E.g. *`walletAddress=0xf0c35891caf1cca9b1dab1291c61ff232e6d5996`*;
* ***Default:*** None;
* ***Scope:*** Applicable for Basic/Premium Partners only;
* ***Required:*** Mandatory for Premium Partners. Optional for Basic Partners;
* ***Signed:*** Mandatory to sign for Premium Partners;
### `walletAddressLocked`
* ***Description:*** *`0`*/*`1`*. *`0`* means user can modify the wallet address. While *`1`* means to display the wallet address but prohibit users from modifying it. It should work pair with *`walletAddress`*. E.g. *`walletAddress=0xf0c35891caf1cca9b1dab1291c61ff232e6d5996&walletAddressLocked=1`*;
* ***Default:*** 0;
* ***Scope:*** Applicable for Premium Partners only;
* ***Required:*** Optional for all partners;
* ***Signed:*** Mandatory to sign for Premium Partners;
### `walletAddressHidden`
* ***Description:*** *`0`*/*`1`*. *`0`* means the wallet address is visible to the user. While *`1`* means the wallet address is invisible. It should work pair with *`walletAddress`*. E.g. *`walletAddress=0xf0c35891caf1cca9b1dab1291c61ff232e6d5996&walletAddressHidden=1`*;
* ***Default:*** 0;
* ***Scope:*** Applicable for Premium Partners only;
* ***Required:*** Optional for all partners;
* ***Signed:*** Mandatory to sign for Premium Partners;
## **Parameters f**or sign up/in page
### `email`
* ***Description:*** Fill in the email address for user on FaTPay widget. Email address field will be left empty if the format validation of email address is failed. E.g. *`email=fatpay@fatpay.xyz`*;
* ***Default:*** None;
* ***Scope:*** Applicable for all partners;
* ***Required:*** Optional for all partners;
* ***Signed:*** Not required to sign;
## Misc parameters
### `windowOpen`
* ***Description:*** It's suggested to append this parameter to get rid of 403 Forbidden iframe error, e.g. *`windowopen=1`*;
* ***Default:*** 0;
* ***Scope:*** Applicable for all partners;
* ***Required:*** Optional for all partners;
* ***Signed:*** Not required to sign;
### `ext`
* ***Description:*** Extended fields;
* ***Default:*** None;
* ***Scope:*** Applicable for all partners;
* ***Required:*** Optional for all partners;
* ***Signed:*** Mandatory to sign for Premium Partners. Should be [urlencoded](https://en.wikipedia.org/wiki/Percent-encoding) before sign;
## **How they work in user flow**
{% hint style="info" %}
You might get a better understanding how these parameters work by checking the following diagram.
{% endhint %}
---
# 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://dev.fatpay.org/reference/integration-tutorial/on-ramp-widget-customization.md?ask=
```
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.
