Introduction to the Criteo OneTag
Criteo OneTag is a single JavaScript snippet that enables Criteo to collect information about user activity on your website (such as product views, add-to-cart actions, and purchases). It powers campaign optimization, product recommendations, audience building, and performance measurement.
Key features of Criteo OneTag include:
Advanced: it triggers automatically visit event to get a stronger user journey.
Lightweight: loads asynchronously to avoid slowing down your site.
Flexible: supports advanced use cases like hashed email collection, cross-device tracking, and audience sharing.
Why use OneTag?
OneTag is essential to activate most of Criteo’s solutions. Without it, Criteo cannot track user behavior and thus cannot:
Deliver personalized ads
Optimize bidding strategies
Provide accurate reporting and measurement
Value it brings:
Smarter targeting: enables real-time audience segmentation based on user behavior.
Better performance: drives higher ROAS through dynamic creatives and product recommendations.
Greater reach: supports alternative identifiers (like hashed emails) to improve reach on browsers with limited cookie support (e.g. Safari, Firefox).
How to access it?
From the left-hand menu of Commerce Growth, click on Assets > Events Tracking.
You can choose how you want to add Criteo OneTag to your website:
E-commerce platform
Google Tag Manager
Direct implementation
How does it work?
Every time someone interacts with your site, OneTag captures that action and sends it to Criteo. This data helps Criteo understand each user's behavior in real time.
For example, if a user views a pair of shoes but doesn’t buy them, Criteo can remember that and later show them an ad with that same product — or similar ones — on other websites or apps.
The more user actions OneTag sees, the more accurate and personalized your ads become. That means your campaigns can focus on the people most likely to click, buy, or return to your site. It also helps improve campaign performance over time, because Criteo’s system keeps learning from each visit.
In short, OneTag helps you turn browsing behavior into smarter advertising — automatically and in real time.