First party data

Learn the difference between first and third party cookies and how they affect your data collection.

First and third-party cookies are both set to track user behavior. While they have similar functions and purposes, they are set, collected, and accessed in different ways.They have similar purposes but are collected AND BLOCKED in different ways.

First-Party Cookies

First-party cookies are set by the website you visit. These cookies enable website owners to collect analytics data, remember user settings, and other functions that improve user experience.

An example of a first-party cookie is when a user signs into an ecommerce website, like Amazon. The web browser will send a request in a process that provides the highest level of trust that the user is directly interacting with Amazon. The web browser saves this data file to the user’s computer, under the “amazon.com” domain. If first-party cookies were blocked, a user would have to sign-in every time they visited, and they wouldn’t be able to purchase multiple items while shopping online because the cart would reset after every item that was added.

Third-Party Cookies

Third-party cookies are created by domains that are not the website (or domain) that you are visiting. These are usually used for online-advertising purposes and placed on a website through a script or tag. A third-party cookie is accessible on any website that loads the third-party server’s code.

Similar to the previous example, third-party cookies work when a user shops on Amazon. They might browse a couple of items and spend some time on the product pages. When the user decides to only purchase one item, the brown hat over the brown shoes, they may later receive emails and other ads for the brown shoes they looked at but never purchased. Even if the user closes their browser and ends the session, that tracking data will still be on their computer.

Differences between First and Third Party Cookies

The main differences between first and third-party cookies include:

  • Setting the cookie: A first-party cookie is set by the publisher’s web server or any JavaScript loaded on the website. A third-party cookie can be set by a third-party server, such as an AdTech vendor, or via code loaded on the publisher’s website.

  • Cookie availability: First-party cookies are available to the domain that created it. A third-party cookie is accessible on any website that loads the third-party server’s code.

  • Browser support/blocking: First-party cookies are supported by all browsers and can be blocked or deleted by the user. Third-party cookies are supported by most browsers, but are blocked by default.

What cookies does AnyTrack sets on the browser

IdentifierExample valueDescription
_atcidas9d8f0a98fUnique anonymous identifier set on the visitor's browser. This cookie has a two years TTL (time to live) and is used to track the visitor's actions, sessions and attribute them to campaigns and conversions.
_atcid-pt1677855987888Timestamp of the session
_atutmcampaign parametersStores the last campaign parameter the visitor came from