# IP Version

By default, our Residential Proxies include both IPv4 and IPv6 addresses. If needed, you can select the Internet Protocol (IP) version to **receive only IPv4 or IPv6 proxies**.

{% hint style="success" %}
To **enable this feature**, contact your Account Manager (details available in the [Dashboard](https://dashboard.oxylabs.io/)). You may need to complete a quick [KYC](https://oxylabs.io/kyc-and-safety) procedure.
{% endhint %}

### Usage

Add the `ipversion` parameter to your username string to specify the IP version. It works alongside other parameters. 

* `ipversion-4` selects proxies from the **IPv4** pool
* `ipversion-6` selects proxies from the **IPv6** pool

For example, if you want to receive only IPv6 proxies, your username string should be: `customer-USERNAME-ipversion-6`. Here's a complete cURL example:

```bash
curl -x pr.oxylabs.io:7777 -U "customer-USERNAME-ipversion-6:PASSWORD" https://ip.oxylabs.io/location
```

{% hint style="warning" %}
Residential Proxies are dynamic, so we cannot guarantee availability when combining the IP version with specific locations (e.g., city, ZIP).
{% endhint %}

If the target website does not support a specific IP version, our system will resolve the supported IP version where possible. For example, if you use the "IPv6 only" parameter with a website that only supports IPv4, the proxy may automatically resolve the target using IPv4 instead.

{% hint style="info" %}
Reach out to your Account Manager to **skip the automatic resolution** and restrict the IP version to the selected one.
{% endhint %}

### Error handling

If the target website does not support IPv6 you have disabled automatic resolution, you will receive a `522` error code. In that case, switch to IPv4 for the specific website or remove the `ipversion` parameter altogether.


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# 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://developers.oxylabs.io/proxies/residential-proxies/advanced-filters/ip-version.md?ask=<question>
```

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.