# Parameters

By appending parameters to the URL of a payment form, you can set default values and thereby personalize the form.

## Overview of All Parameters

The following overview shows which parameters are available in the various forms.

### Global parameters

The following parameters work across all [e-commerce tools](/merchant/english/account/tools.md) in Payrexx:

| **Name**                                                           | **Parameter**     |
| ------------------------------------------------------------------ | ----------------- |
| Amount (Default)                                                   | invoice\_amount   |
| Amount ([Terminal](/merchant/english/account/tools/terminal.md))   | amount            |
| Currency (Default)                                                 | invoice\_currency |
| Currency ([Terminal](/merchant/english/account/tools/terminal.md)) | currency          |
| Purpose (Default)                                                  | invoice\_number   |
| Purpose ([Terminal](/merchant/english/account/tools/terminal.md))  | purpose           |
| Salutation                                                         | contact\_title    |
| First name                                                         | contact\_forename |
| Last name                                                          | contact\_surname  |
| Company                                                            | contact\_company  |
| Street                                                             | contact\_street   |
| ZIP Code                                                           | contact\_postcode |
| Place                                                              | contact\_place    |
| Country                                                            | contact\_country  |
| Phone                                                              | contact\_phone    |
| Email                                                              | contact\_email    |
| Text field content                                                 | contact\_text     |
| Multiline text field content                                       | contact\_textbox  |
| Discount code                                                      | code              |
| Reference                                                          | referenceId       |

### Parameters for the Donation tool

The following parameters work only in the "Donation" tool:

| **Description**                                                                                                                                     | **Parameter**                  |
| --------------------------------------------------------------------------------------------------------------------------------------------------- | ------------------------------ |
| <p>The amount of 50 is proposed. Can be changed by the donor.</p><p>\[<strong>Values:</strong> Amount, amount with decimal point (e.g. 10.50)].</p> | donation\[preselect\_amount]   |
| <p>Interval is selected. Can no longer be changed.</p><p>\[<strong>Values:</strong> one\_time, weekly, monthly, quarterly, annually]</p>            | donation\[interval]            |
| <p>Interval is proposed. Can still be changed by the donor.</p><p>\[<strong>Values:</strong> one\_time, weekly, monthly, quarterly, annually]</p>   | donation\[preselect\_interval] |
| <p>The purpose of the donation is pre-selected and can be changed by the donor.</p><p>\[<strong>Values:</strong> 1,2,3,...]</p>                     | donation\[preselect\_purpose]  |
| <p>The campaign description is hidden.</p><p>\[<strong>Values:</strong> 0.1]</p>                                                                    | hide\_description              |

## Examples of Using URL Parameters

The following examples illustrate how you can use URL parameters with Payrexx [e-commerce tools](/merchant/english/account/tools.md).

{% hint style="info" %}
A question mark (**?**) must precede the first URL parameter, and each additional parameter is introduced with an **&**.
{% endhint %}

<table><thead><tr><th width="336.40740966796875">Link with URL parameters</th><th>Function</th></tr></thead><tbody><tr><td>https://[instance].payrexx.com/en/vpos<strong>?amount=19.50</strong></td><td>When the <a href="/pages/-MZwweoXEZ85kpczvajC">terminal</a> is opened, the amount of 19.50 is pre-defined.</td></tr><tr><td>https://[instance].payrexx.com/en/vpos<strong>?amount=19.50&#x26;purpose=Test</strong></td><td>When the <a href="/pages/-MZwweoXEZ85kpczvajC">terminal</a> is opened, the amount of 19.50 and the payment purpose “Test order” are pre-defined.</td></tr><tr><td>https://[instance].payrexx.com/en/pay?tid=fbd71f97<strong>&#x26;contact_title=Mr&#x26;contact_forename=John&#x26;contact_surname=Smith</strong></td><td>When the payment <a href="/pages/-MZCk2Yb-SBlLK557d6C">page</a> is opened, the fields "Title", "First name", and "Last name" are automatically populated with "Mr", "John", and "Smith".</td></tr><tr><td>https://[instance].payrexx.com/en/pay?cid=74eb3a66<strong>&#x26;donation[preselect_amount]=50</strong></td><td>When the <a href="/pages/-MZCkGC9VaZS6YR9TF-D">donation</a> page is opened, the amount of 50.00 is automatically selected, but can still be modified by the donor.</td></tr></tbody></table>


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