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

# Data collection (backend)

> Reference guide for all data stored on Kameleoon back-end servers, covering analytics data, synchronization fields, and retention behavior.

If you want to learn which data is stored **client-side**, in the visitor's browser, refer to the [data collection client-side](./data-collection-client-side) article.

<Note>
  This article primarily applies to **Kameleoon Web Experimentation** or when using [Kameleoon Hybrid Experimentation mode](../feature-experimentation/targeting-and-segmentation/native-segmentation#hybrid-experimentation-mode).

  If you are only using Kameleoon's SDKs (Feature Experimentation), **no data will be collected** except:

  * Data that is **explicitly sent** using the `addData` method of the SDK.
  * All **exposure events** related to feature flag evaluations.
</Note>

## List of collected data[​](#list-of-collected-data "Direct link to List of collected data")

The following data is collected and stored on Kameleoon back-end servers for each visit made by an individual visitor to your website:

* **Visitor code** (a unique Kameleoon identifier for this visitor)
* **Visit number** (if multiple visits were made by the same visitor)
* **Device type** (mobile, tablet, or desktop)
* **Operating system** (Windows, macOS, Linux)
* **Browser name and version**
* **Screen size**
* **Window size**
* **Browser time zone**
* **Browser language**
* **Original referrer** (acquisition channel)
* **Number of pages viewed**
* **Time elapsed since the visitor's previous visit** (if any)
* **Time spent on the website**
* **Start and end time of the visit**
* **Number of mouse clicks**
* **Ad blocker detection** (enabled/disabled)
* **List of conversions** (for example, clicks, transactions), including revenue (if applicable)
* **List of personalizations and A/B experiments** seen by the visitor
* **List of targeted Kameleoon segments** (requires [Audiences Explorer](/user-manual/ai-opportunity-detection/audiences-segment-analysis)
* **Current weather conditions** (if the corresponding targeting condition is activated): temperature, wind, rain, and other conditions.
* **Sunset and sunrise times** (required for some weather-based targeting criteria)
* **Geolocation** (only if a corresponding targeting condition is activated, as some weather-related criteria require geolocation data)
* **Products viewed** (only if the add-on is enabled)
* **Titles and URLs of pages visited**
* **Custom data**
* **External segmentation data** (obtained from a third-party DMP or CRM)
* **Conversion probabilities** computed by the **Kameleoon AI Predictive targeting engine** (only when at least one AI-driven personalization is active; required for generating Kameleoon Conversion Score heat ranges)

<Note>
  By default, **Kameleoon does NOT collect any personal information** as defined by **GDPR** or similar data privacy laws. However, personal data may still be collected and stored on Kameleoon back-end servers in the following cases:

  * Your URLs contain parameters with personal data, as Kameleoon collects visited URLs. Kameleoon strongly recommends removing such parameters from your URLs, as they are collected by all web analytics platforms.
  * You explicitly define a [custom data](../custom-data) field and populate it with personal data.
  * You explicitly configure an integration with a third-party DMP or CRM that provides personal data.

  Kameleoon will never store any IP addresses on its data servers. There are no exceptions to this rule: even when legal consent has been provided by a visitor, IP addresses are not saved.
</Note>

## Data retention policy[​](#data-retention-policy "Direct link to Data retention policy")

Kameleoon retains visit and product event data for **24 months** for analytics purposes. The retention period begins when the first event is processed. If you require a shorter retention period, please contact your Customer Success Manager.

<Note>
  * [Cross-Device Experimentation](../cross-device-experimentation): 3 months of prior data can be retrieved for targeting in Web Experimentation and Feature Experimentation.
  * [ITP Management](../web-experimentation/technical-concepts/itp-management): 3 months of prior data can be retrieved for targeting in Web Experimentation and Feature Experimentation.
  * Remote Synchronization of Visits: 3 months of prior data can be retrieved for targeting in Web Experimentation and Feature Experimentation.
  * AI Predictive Targeting: 3 months of prior data are used to compute Kameleoon Conversion Scores.
  * Product Targeting: 3 months of prior data can be retrieved for targeting in Web Experimentation.
  * Data API MAP Endpoint: 1 year of prior data can be retrieved in Web Experimentation and Feature Experimentation.
</Note>