---
title: "Data Passback"
slug: "data-passback"
tags: ["Data Pass Back", "Rule Events", "Variables", "ROAS"]
updated: 2026-01-08T14:01:11Z
published: 2026-01-08T14:01:11Z
canonical: "help.quantcast.com/data-passback"
---

> ## Documentation Index
> Fetch the complete documentation index at: https://help.quantcast.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Data Passback

Event parameters are an optional JSON-formatted object that you can include when tracking standard and custom events. They allow you to provide additional information about your website visitors' actions for reporting and/or targeting. Once tracked, parameters can be used to further define any custom audiences you create based on a pixel event or to track special metrics such as Return On Ad Spend (ROAS).

> **Note**: The “revenue” variable is required to track ROAS.

```plaintext
<script type="text/javascript">
    window._qevents = window._qevents || [];
    window._qevents.push({
        qacct:"p-123456789",  // your pcode
        labels:"_fp.event.Purchase", orderid:"12345",revenue:"100.00",
        event:"refresh"
    });
</script>
```

## **Parameter Variables**

> **Note**: This is a sample only; do not implement this code on your website.

| **Variable** | **Description** |
| --- | --- |
| orderid | Your unique identifier for a customer order. |
| revenue | The total value of the conversion. (required for ROAS) |
| pcat | The product category of the event. |
| customer | The customer type/segment that triggered the event. |

## **Custom Variables**

If our predefined variables don't suit your needs, you can include your own custom variables. Custom variables can be used with both standard and custom events and can help you further define a Pixel Audience.

For example, to track a visitor who purchases a specific product type. You could do this:

```plaintext
<script type="text/javascript">
    window._qevents = window._qevents || [];
    window._qevents.push({
        qacct:"p-123456789", // your pcode
        labels:"_fp.event.Purchase.sneakers-casual",
        orderid:"12345",
        revenue:"100.00",
        event:"refresh"
    });
</script>
```

> **Note**: This is a sample only; do not implement this code on your website.

When configuring data passback, please be sure the data you are passing to Quantcast complies with our applicable [Term](https://www.quantcast.com/terms/measure-terms-service/.)[s of Service.](https://legal.quantcast.com/#measure-publisher-terms-of-service)