Comparing Universal Analytics (UA) and Google Analytics 4 (GA4)

Here’s a simplified glossary and transitional guide for a longtime Universal Analytics (UA) user transitioning to Google Analytics 4 (GA4):

Events vs. Hits

  • UA (Hits): In UA, tracking is based on “hits” (pageviews, events, transactions, etc.). Each hit has its own type and purpose.
  • GA4 (Events): Everything in GA4 is an event. Pageviews, clicks, form submissions, and even transactions are all tracked as events. This simplifies the tracking system and offers more flexibility in customizing events.

Goals vs. Conversions

  • UA (Goals): UA allowed you to set specific goals based on user actions (like form submissions or page views). These were limited to 20 per view.
  • GA4 (Conversions): In GA4, any event can be marked as a conversion (like a form submission, purchase, or signup). You can mark multiple events as conversions, without the same restrictions as UA.

Sessions

  • UA (Sessions): A session in UA is a group of interactions that happen within a specific timeframe (e.g., 30 minutes). UA sessions reset when a campaign source changes.
  • GA4 (Sessions): GA4 sessions work similarly but don’t reset as easily (e.g., changing campaign sources doesn’t restart the session). GA4 uses session_start events to track them, offering more consistency in reporting.

Bounce Rate vs. Engagement Rate

  • UA (Bounce Rate): In UA, bounce rate measured the percentage of sessions where users only viewed one page and then left.
  • GA4 (Engagement Rate): GA4 focuses on engagement rather than bounces. The engagement rate measures how many users interact with the site (e.g., staying for 10+ seconds, viewing 2+ pages, or triggering a conversion event). It offers a more meaningful view of user activity.

User Identification

  • UA (Client ID): UA used client IDs (stored in cookies) to track anonymous users across sessions.
  • GA4 (User ID + Client ID): GA4 uses a combination of User IDs (for logged-in users) and Client IDs (for anonymous users) to track users. It’s designed to handle cross-device tracking more seamlessly.

Reports

  • UA (Predefined Reports): UA provided predefined reports like Audience, Acquisition, Behavior, and Conversions.
  • GA4 (Customizable Reports): GA4 offers more customizable reporting options through the Explore section, where you can create detailed, flexible reports using any combination of dimensions and metrics.

Enhanced Measurement

  • UA (Event Tracking Setup): In UA, tracking specific actions (e.g., clicks or video views) required manual event tracking setup in your code or Google Tag Manager.
  • GA4 (Enhanced Measurement): GA4 automatically tracks common interactions (like scrolls, outbound clicks, video engagement, file downloads) without the need for additional setup.

Data Model

  • UA (Session-Based): UA’s data model was largely session-based, grouping user interactions into discrete sessions.
  • GA4 (Event-Based): GA4 is event-based, meaning every action a user takes is captured as an event, giving more granular control over what you track and how it’s analyzed.

Attribution

  • UA (Last-Click Attribution): UA used last-click attribution by default, meaning the last channel to send a user to your site received all the credit for conversions.
  • GA4 (Data-Driven Attribution): GA4 defaults to data-driven attribution, which uses machine learning to assign credit to multiple touchpoints in the user journey, offering a more holistic view of marketing performance.

Audience Creation

  • UA (Segments and Audiences): In UA, you could create audiences and segments to group users based on specific criteria (e.g., by behavior or demographics).
  • GA4 (Audiences and Segments): In GA4, audience creation is more powerful and integrated with Google Ads. You can define audiences based on events, and GA4 offers better cross-device tracking for these groups.

Debugging Tools

  • UA (Real-Time Reports): UA offered real-time reports to see current users and their interactions.
  • GA4 (DebugView): GA4 includes DebugView, where you can track events as they happen on your site or app. This is especially useful when testing tracking configurations.

Custom Dimensions and Metrics

  • UA (Custom Dimensions): UA allowed custom dimensions and metrics but required manual setup and was limited in flexibility.
  • GA4 (Event Parameters): GA4 replaces custom dimensions with event parameters. Each event can have additional parameters (like page title, button text) for more flexibility and detail in your reporting.

Views

  • UA (Views): UA allowed multiple views within a property to segment data for different needs (e.g., filtered views for different countries).
  • GA4 (No Views): GA4 doesn’t use views. Instead, it relies on data streams (web, app, etc.) and filters to customize what data is shown. Custom reporting can segment the data without the need for views.

Key Takeaways

  • Simplified Tracking: Everything is tracked as an event in GA4, giving you more control over what to monitor.
  • Cross-Platform: GA4 unifies web and app data into one property for better cross-device tracking.
  • Privacy and Future-Proofing: GA4 is designed for a future without third-party cookies, using machine learning to fill gaps in user data.
  • More Flexibility: Customizable reports and event tracking give more granular insight compared to UA’s more rigid structure.

Please reach out if you’d like to discuss how Google Analytics 4 is measuring your site’s current activity.

Caryn Solly
Caryn Solly
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