About Pixel Tracking

Pixel tracking—also called “cookie-based tracking” and “client-side tracking”—is the method of tracking conversions that uses the user’s browser rather than the advertiser’s server (as server postback tracking does).

This article explains pixel tracking in detail, and builds on the following articles:

The Flow of Pixel Tracking

As discussed in the Attribution Methods in TUNE article, pixel tracking can be thought of as two separate processes: what happens when a user clicks on an offer and what happens on conversion.

Leading up to the conversion:

  1. User sees an offer.
  2. User clicks on the offer, and TUNE records the click.
  3. TUNE generates and stores the transaction ID for that session in a cookie in the user’s browser.
  4. TUNE immediately directs the user to the offer’s landing page.

As the user goes through the advertiser’s site, they may make a purchase or take another action that defines the conversion. Typically, conversions are measured on a “Thank You” or other page after the action takes place. Users who do not accept cookies in their browser are not measured by offers using pixel tracking.

When the user converts on that offer:

  1. User’s browser loads a 1 pixel by 1 pixel HTML container (the “pixel” or “conversion pixel”) which houses an offer’s conversion link. During offer setup, the advertiser placed this pixel on the page that measures the conversion.
  2. Conversion pixel sends a signal to TUNE that includes the session identifier in the user’s browser cookie. The user is not directed to TUNE in any way.
  3. If the session identifier matches the one generated by TUNE at the time of the click, then TUNE records a conversion for that session.

When to Use Pixel Tracking

TUNE’s general recommendation is to use pixel tracking as little as possible, as pixel tracking only works for non-mobile web traffic where cookies can be stored. Additionally, major browsers like Safari are moving away from allowing tracking-related cookies even for first parties.

As the last resort, use pixel tracking if the following are true:

  • The offer’s advertiser is unable to send server-side conversion notifications.
  • The offer does not involve mobile app installs.
  • The offer’s desired end users are on browsers that support tracking-related cookies.

Pixel Tracking Protocols

There are four protocols for pixel tracking, based on the HTML iframe or image tags. All pixel tracking protocols track click sessions using cookies, and are subject to the limitations imposed on cookies by web browsers.

Best practice is to use the “HTTPS iframe pixel” protocol for cookie-based conversion tracking.

Security Protocols (HTTPS vs HTTP Pixel)

Many browsers like Chrome detect and label sites if they are unsecure. You can tell a site is secure if the URL begins with “https://” instead of “http://”. These browsers only load secure content from secure sites. HTTP iframe and image pixels are not secured content, so secure sites will block them as well.

Tip: TUNE provides the default go2cloud.org tracking domain on a secure server, so you can use HTTPS pixel protocols to track offers on secure pages. To secure your custom tracking domain, reach out to your account manager.

HTML Containers (iframe vs Image Pixel)

Pixel tracking protocols use either an HTML iframe or image tag to contain an offer’s conversion link and to fire partner conversion links. If your advertiser can use an iframe conversion pixel over an image pixel, then there is no reason to use an image pixel protocol.

Image pixels are the legacy tracking protocol, and are provided only as a way to integrate with tracking systems that can’t support other attribution methods. Image pixels also have additional limitations like only being able to load a single partner conversion pixel, and being unable to load partner iframe conversion pixels.

Pixel Implementation in Brief

Implementing a conversion pixel also involves some steps outside of TUNE. Here are the key steps of that process:

  1. Find the automatically generated conversion pixel for the offer in TUNE.
    • On the offer’s page, find the Details panel and click Tracking. For offers with goals, instead find the Payout panel and click View next to the relevant goal.
  2. Copy the HTML “Pixel Code”, which contains the conversion link.
  3. Send the pixel code to the advertiser, or whoever manages the offer conversion page.
  4. The advertiser places the pixel code on the conversion page.
  5. When a user converts, the conversion pixel loads and validates the session via the user’s browser cookies.

Note: If an offer’s tracking protocol or tracking domain changes, then the pixel code must be updated and resubmitted to the advertiser for placement.

Cookieless Tracking with Pixels

While uncommon, you may encounter a situation where your advertiser can send server-side conversion notifications but your partners are unable to accept postbacks. The advertiser’s site must be able to store a transaction ID in some way, such as storing it as a variable in an e-commerce site or SDK in a mobile app. In those cases, it’s possible to set up an offer to use pixel tracking without cookies.

You can set up cookieless pixel tracking by forwarding session transaction IDs using the {transaction_id} macro to your advertiser in the offer URL. Then in the conversion pixel, your advertiser must return the ID in the transaction ID parameter:

<iframe src="https://demo.go2cloud.org/aff_l?offer_id=100&transaction_id=1a2b3c4d" scrolling="no" frameborder="0" width="1" height="1"></iframe>

When cookieless tracking is used to record a conversion, the status message “Server Postback Tracking” appears for the conversion even though the offer uses client-side tracking.