Pixel Management

A pixel is a 1x1 transparent image that is loaded when a user visits a web page. Under the hood, it is an HTML or Javascript code snippet with the link to a pixel server. When a user visits a page, the browser executes the code and follows the link so that we register a conversion or another event.

Pixels can be used for two purposes: collecting audience segments and tracking events.

To create a new pixel, use the following steps.

  1. Select Pixels ‣ Create New

  2. Enter the pixel Name into the relevant field.

  3. Assign the pixel to an Advertiser by selecting the relevant advertiser from the dropdown list.

  4. If you want your pixel to track in-app events, please provide the following information:

    • Enter the Event Name into the relevant field.

    • Fill the Apple Bundle IDs field, entering one bundle ID each row. This is a required field in case an Event Name was provided. BidCore requires event names and bundle IDs for in-app tracking so the pixel can be identified when the id parameter is missing in the /pixel call from mobile management platforms.

    Make sure your in-app tracking pixel is Server-to-Server, see details further in this section.

    If your pixel doesn’t track in-app events, leave these two fields empty.

  5. Activate the Pixel collects User Segment checkbox if you want the pixel to collect user segments for retargeting campaigns.

    When the checkbox is activated, the segment life parameter becomes available. Segment life (the lifetime of a segment) must have a non-zero value. For example, setting its value to 30 days means that every segment will be stored for 30 days for each user. Each user will be available for retargeting during these 30 days.

    Pixels that collect user segments can be used as impression trackers for line item retargeting. Refer to the 3rd Party Impression Trackers section for detailed information.

  6. Activate the Pixel is Server-to-Server checkbox if you want the pixel to track server-to-server events.

    Server-to-server events don’t come from the user’s browser. In the typical flow of event tracking or audience collecting, users get to a web page, the pixel is triggered, the cookie is read, then either a conversion is attributed or a segment recorded for this user with the user ID taken from the cookie. But in case of some events, the trackable event cannot be put on the website.

    In case when the trackable event takes place on a web site, we try to set a cookie whenever a user triggers the pixel and a cookie isn’t set. After this, a redirect response is issued so that the request is redirected to the same handler again. But first of all there is a check whether the cookie can be set at all. When a request doesn’t come from a browser, there is no cookie, and in case there is no information about the request being server-to-server, we try to set it, the redirect is not performed properly and the conversion is lost. This is what Server-to-server checkbox is for: to let us know that the request is not coming from a browser, so we don’t try to set a cookie.

    When a cookie cannot be set, some parameter is still required to be used for conversion attribution. It can be, for example, a user ID or a click ID. To attribute a conversion to a particular event, the ${ONLINE_CONVERSION_CONTEXT} macro is used - the automatically generated pixel code for server-to-server pixels contains this macro. Whenever a line item is set to track server-to-server events, the ${ONLINE_CONVERSION_CONTEXT} macro should be present in the creatives’ Click URL.

    The Pixel is Server-to-Server checkbox is often used for tracking app installation events, but its use is not limited by them. Any conversion event that doesn’t happen in a browser can be server-to-server; for example when a user fills in some form, but the actual conversion happens when this form is processed by the advertiser. Generally, the less access we have to cookies, the more popular tracking conversions by their online context will become.

  7. Activate the Pixel is Install Tracking checkbox if you want the pixel to track app installation events.

    App installation events come from attribution systems. These systems perform attribution on their side and send a signal that an installation event has taken place. In most cases app installation events are server-to-server.

  8. Set up the GDPR compliance of your pixel by selecting either non-GDPR or GDPR (EU) option. If you set your pixel up as GDPR compliant, BidCore will only process the user’s personal data in case of consent given. If no consent given, the user’s personal data will be removed from processing. The following data is treated as personal:

    • The user’s IP address

    • The user’s cookie

    • The user agent (browser version)

    GDPR compliant pixels have GDPR specific macros added to their code, see the Markup Substitution Macros section for details.

  9. Save New Pixel.

After the pixel is saved, the system generates code for this pixel. The pixel code can be copied and placed appropriately in your page code.

Options for further pixel customization are available in the line item setup interface. The same pixel can be used with multiple line items and have different properties assigned, depending on the line item and its goals.

To assign a pixel to a line item and further customize it, please proceed as follows.

  1. On the Line Item customization screen, proceed to the Buying Strategy ‣ Event Tracking block and press Add Tracking Pixel.

  2. Assign a pixel to the line item by selecting it from the Tracking Pixel dropdown list.

  3. Select the tracking event type by activating Conversion or Landing radio button. Conversion is selected by default.

    Conversion is any action taken by the user after interacting with your ad that you define as valuable for your campaign goals.

    Landing is an event that happens right after the user clicks on an ad - the user is redirected to the landing page. A landing tracking pixel can be triggered immediately or after the user spends some time (several seconds) on the landing page.

  4. The Optimize checkbox is required for strategies with event optimization. Make sure you only activate it for pixels that track the event optimized by the selected optimization strategy.

    At this point only conversions can be optimized. The Conversion event type may include different events that don’t qualify as Landing or Install.

  5. Set values for Post Click Attribution Window and Post View Attribution Window.

    These values are important for optimization. The general rule is that the larger the conversion attribution window is, the more difficult it is to optimize the conversion. Conversions taking place a month after the impression was served are really hard to optimize and predict. It is much easier with instant attribution, with conversions taking place within a day or two after the impression was served.

    For performance campaigns we recommend to set up small attribution windows for better prediction. Large attribution windows may look good in reporting as they pick up more conversions, but they are much less useful for optimization purposes.


Pixel signals are used by u-Slicer for tracking the following events:

  • Landings

  • Post-view Conversions

  • Post-click Conversions

  • Attributed PVC

  • Attributed PCC

Also, pixel signals are used for tracking segment collection:

  • Pixel Segments

See the Reporting Overview section for detailed information about u-Slicer.