Getting the Data You Need with Cookies, Pixels and IDs

June 12, 2018 Ginna Hall

Remember shoe shopping in 1990? When you needed a new pair of shoes, you would drive to the shoe store or the mall. You’d see what they had in the store and try on a few pairs. You bought the one pair you liked in your size. You drove home and hoped they didn’t give you blisters.

Compare that with shoe shopping in 2018. Now, when you need a pair of shoes, you bring up the Zappos app on your phone. You search by brand and style. You filter by size and color. You end up with 142 possible choices.

Later that day, you see an email in your inbox and click through to the Zappos site on your laptop. You do a search and scroll through the options. Later, you fire up your desktop, search for the exact shoe you want and save three pairs to your cart. They arrive the next day. You try them all on and return the two you don’t want.

Download our ebrief “How Cookies, Pixels and IDs Help You Get the Data You Need” to learn more about how each tracking technology works and when to use each type.

There is no single path-to-purchase

Digital technology, mobile devices and wireless broadband have created a world in which each consumer follows their own unique path-to-purchase for every product or service. In this landscape, developing a people-based marketing strategy is challenging. Especially since some companies have millions of customers, each with their own individual paths to conversion.

But technology also offers a helping hand to marketers by enabling us to monitor and measure each stop on the journey -- the “touchpoints” where a brand and its buyer meet.

By identifying these touchpoints -- and understanding how each one influences conversions, revenue and other desired outcomes -- marketers can create consistent experiences and better allocate resources to engage customers along the way.

This “multi-touch” attribution has shed new light on the consumer journey and how marketers can make better use of their marketing dollars. But how do today’s sophisticated analytics platforms actually track individual users?

Marketers need to identify consumers across every touchpoint

We all leave digital footprints online. Each touchpoint generates its own unique ID so that it could recognize the individual on any return visits.

There are several tracking technologies that make this possible. The most common types include cookies, click redirects, image tags, site tags and unique identifiers.​

Download our ebrief “How Cookies, Pixels and IDs Help You Get the Data You Need” to learn more about how each tracking technology works and when to use each type.


A cookie is a small piece of data sent from a website and stored in a user’s web browser while the user is browsing that website.

Pro: A cookie can track the websites a person visits afterwards, their behavior, and their purchases.

Con: Cookies aren’t persistent. Any media that runs in a mobile app is cookieless and requires a device ID to tie it to a user.


Click redirects briefly send a user through the ad server to be “cookied” before passing them through to their desired landing page.

Pro: ​Click redirects are good for marketing or media running outside an ad server such as email marketing or paid search.

Con: Because it sends the user through the ad server to be “cookied” it may not work in a cookieless environment.


Pixel tags are single pixel, transparent GIF images that are added to a web page and served like any other image online.

Pro: A virtually invisible tag that is served just like any other image you may see online, it allows marketers to retain control over tracking

Con: Tag must be added to each web page to allow tracking.


Site tags use JavaScript to control the information being passed into a pixel tag and can decide whether or not to “fire” the pixel tag.

Pro: Able to track users that arrive at a website from earned and owned marketing channels such as organic search visits and direct traffic and otherwise otherwise untracked touchpoints.

Con: Tag technologies are browser-bound. Each cookie only lives on its own browser on its own device.


Mar Tech and Ad Tech systems (ad servers, email platforms, CRM systems, third-party data providers, and more) create their own unique ID to identify customers across multiple touchpoints.

Pro: Each ID contains valuable user interaction data and insight across online and offline channels.

Con: Because they are stored separately and unique to each system, users may have multiple IDs, making it difficult to follow someone across channels and devices.

What’s in store for the future of tracking technologies?

Alternative methods to serve ads without cookies are already well underway. One of these techniques is known as “fingerprinting.” Your browser transmits a variety of information that is not related to cookies. Fingerprinting allows a site to look at the characteristics of a computer such as the plugins and software you have installed, the size of the screen, timezone, fonts and other features of a particular machine.

By combining these elements to form a unique identity, an individual can be assigned an identifying number which can be used just like a cookie. While device fingerprinting is growing in popularity, additional development is needed to resolve issues of standards, accuracy and cross-device tracking.

Choose which tracking technology to use

Cookies, pixels, site tags and IDs are some of ways marketers can track consumer journeys across channels and devices for multi-touch attribution. Multi-touch attribution calculates the fractional credit due to each touchpoint that contributed to a lead, download, sale or some other key performance indicator (KPI).

Learning which tracking technology to use for attribution is important for digital marketers. Some are more compatible with certain platforms and publishers than others.

A recent example is Google’s announcement that it has made significant changes to the way it will handle IDs in DoubleClick.

>> Read Using Pixels and Tags in the Wake of DoubleClick Cookie Limits to learn more. <<

Fortunately, pixels and tags are two alternatives to ad server cookies that can help marketers continue to measure performance data despite the ID restrictions in DoubleClick.

Pixels and tags offer several unique benefits when compared to a cookie ad server approach, such as increased access to data sources; higher match rates between core measurement data and partner infrastructure; and identical taxonomy rules and cost sources.

Measure marketing effectiveness in the digital era

Using unique identifiers for multi-touch attribution means being able to target valuable audiences with greater precision than ever before. With access to robust audience profiles, marketers can carefully coordinate the customer experience across their paid, owned and earned channels, and deliver the right message to the right person, at the right time and place.

Learn More

Download our ebrief “How Cookies, Pixels and IDs Help You Get the Data You Need” to learn more about how each tracking technology works and when to use each type.

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