Google Analytics 4 Complete Setup Guide: 2025 Best Practices

What is Google Analytics 4?

Google Analytics 4 (GA4) is the latest generation of Google's web analytics platform, replacing Universal Analytics which was sunset in July 2023. GA4 represents a fundamental shift in how we track and understand user behavior on websites and mobile apps. At Digital Applied, we help businesses leverage GA4's full potential to make data-driven marketing decisions.

Key Differences from Universal Analytics

Event-Based Model: Everything is tracked as an event, providing more flexibility than the session-based model
Cross-Platform Tracking: Unified tracking for web and mobile apps in a single property
AI-Powered Insights: Machine learning predicts user behavior and identifies trends automatically
Privacy-First Design: Built-in privacy controls and compliance with GDPR and other regulations
Enhanced Integration: Deeper connection with Google Ads for better attribution

GA4 Adoption in 2025

Universal Analytics was sunset in July 2023, and as of 2025, GA4 is now the standard analytics platform used by millions of websites worldwide. According to BuiltWith, GA4 has achieved widespread adoption with mature documentation and extensive community support.

Setting Up GA4 Property

Creating a GA4 property is straightforward, but proper configuration from the start saves significant troubleshooting later.

Step 1: Create GA4 Property

Navigate to Google Analytics and click Admin
In the Property column, click Create Property
Enter your property name and reporting timezone
Select your industry category and business size
Choose your business objectives (this customizes your reports)

Step 2: Set Up Data Stream

Data streams are how GA4 receives data from your website or app. For web properties:

Select Web as your platform
Enter your website URL and stream name
Enable enhanced measurement (tracks page views, scrolls, outbound clicks, site search, video engagement, and file downloads automatically)
Copy your Measurement ID (format: G-XXXXXXXXXX)

Pro Tip: Enable enhanced measurement from day one. It tracks common interactions automatically without requiring code changes, giving you valuable data immediately.

Step 3: Install Tracking Code

You can install GA4 tracking using Google Tag Manager (recommended for flexibility) or directly via gtag.js. For direct implementation, add this to your site's <head>:

<!-- Google tag (gtag.js) -->
<script async src="https://www.googletagmanager.com/gtag/js?id=G-XXXXXXXXXX"></script>
<script>
  window.dataLayer = window.dataLayer || [];
  function gtag(){dataLayer.push(arguments);}
  gtag('js', new Date());
  gtag('config', 'G-XXXXXXXXXX');
</script>

Event Tracking Fundamentals

GA4's event-based model means every interaction is tracked as an event with parameters. Even a simple page view is an event named page_view.

Event Categories

Automatically Collected Events

These events are tracked automatically when you install GA4: page_view, session_start, first_visit, user_engagement, and more. No configuration needed.

Enhanced Measurement Events

When enabled, tracks scroll (90% page scroll), click (outbound links), view_search_results, video_start, video_progress, video_complete, and file_download events.

Recommended Events

Google's predefined events with specific names and parameters: login, sign_up, purchase, add_to_cart, etc. Use these for better Google Ads integration.

Custom Events

Events you create with your own names and parameters. Only use when no recommended event fits your needs.

Tracking Custom Events

To track a custom event, use the gtag function:

// Basic event tracking
gtag('event', 'button_click', {
  'event_category': 'engagement',
  'event_label': 'cta_button',
  'value': 1
});

// Recommended event (login)
gtag('event', 'login', {
  'method': 'Google'
});

Best Practice: Always use recommended events when possible. They integrate seamlessly with Google Ads and appear in built-in GA4 reports without custom configuration.

Configuring Key Events

In 2024, Google renamed "Conversions" to "Key Events" across GA4. Key events are important actions that measure business success: purchases, form submissions, sign-ups, downloads, etc.

How to Mark Events as Key Events

Navigate to Admin in GA4
Select Data Display, then Events
Find the event you want to mark (it must have been triggered at least once)
Toggle the star icon to mark it as a key event
Key events appear in conversion reports and Google Ads

Important: Events must be tracked at least once before you can mark them as key events. Set up event tracking first, test it, then configure key events.

Common Key Events to Track

eCommerce: purchase, add_to_cart, begin_checkout
Lead Generation: generate_lead, form_submit, contact_request
Engagement: sign_up, login, file_download
Content: video_complete, scroll (90%), content_engagement

Key Events in Google Ads

When you mark events as key events in GA4, they automatically sync to your linked Google Ads account as conversions. This enables conversion tracking, smart bidding optimization, and performance measurement directly in your ad campaigns without additional configuration.

eCommerce Tracking Setup

GA4 eCommerce tracking follows Google's recommended events standard, providing detailed revenue attribution and product performance insights. For businesses running online stores, proper eCommerce tracking is essential to understand customer behavior and optimize conversion rates. Our eCommerce solutions include complete GA4 eCommerce tracking implementation.

Essential eCommerce Events

// View item
gtag('event', 'view_item', {
  currency: 'USD',
  value: 29.99,
  items: [{
    item_id: 'SKU_12345',
    item_name: 'Premium Widget',
    item_category: 'Widgets',
    price: 29.99,
    quantity: 1
  }]
});

// Add to cart
gtag('event', 'add_to_cart', {
  currency: 'USD',
  value: 29.99,
  items: [{
    item_id: 'SKU_12345',
    item_name: 'Premium Widget',
    price: 29.99,
    quantity: 1
  }]
});

// Purchase
gtag('event', 'purchase', {
  transaction_id: 'T_12345',
  value: 29.99,
  tax: 2.40,
  shipping: 5.00,
  currency: 'USD',
  items: [{
    item_id: 'SKU_12345',
    item_name: 'Premium Widget',
    price: 29.99,
    quantity: 1
  }]
});

eCommerce Event Sequence

view_item_list: User views product category or search results
view_item: User views product detail page
add_to_cart: User adds item to shopping cart
begin_checkout: User starts checkout process
add_payment_info: User enters payment details
purchase: Transaction completed successfully

Critical: Use exact recommended event names and parameters. Variations won't populate built-in eCommerce reports or sync properly with Google Ads.

Next.js Integration Example

Implementing GA4 in Next.js requires handling both server and client components. Here's a production-ready setup for Next.js 15. If you need assistance implementing analytics on your website, explore our web development services for expert implementation.

1. Create GA4 Script Component

// lib/analytics.tsx
import Script from 'next/script';

export function GoogleAnalytics() {
  const GA_ID = process.env.NEXT_PUBLIC_GA_ID;

  if (!GA_ID) return null;

  return (
    <>
      <Script
        src={`https://www.googletagmanager.com/gtag/js?id=${GA_ID}`}
        strategy="afterInteractive"
      />
      <Script id="google-analytics" strategy="afterInteractive">
        {`
          window.dataLayer = window.dataLayer || [];
          function gtag(){dataLayer.push(arguments);}
          gtag('js', new Date());
          gtag('config', '${GA_ID}', {
            page_path: window.location.pathname,
          });
        `}
      </Script>
    </>
  );
}

2. Add to Root Layout

// app/layout.tsx
import { GoogleAnalytics } from '@/lib/analytics';

export default function RootLayout({
  children,
}: {
  children: React.ReactNode;
}) {
  return (
    <html lang="en">
      <body>
        {children}
        <GoogleAnalytics />
      </body>
    </html>
  );
}

3. Track Custom Events

// lib/analytics-events.ts
export const trackEvent = (
  eventName: string,
  eventParams?: Record<string, any>
) => {
  if (typeof window !== 'undefined' && window.gtag) {
    window.gtag('event', eventName, eventParams);
  }
};

// Usage in components
import { trackEvent } from '@/lib/analytics-events';

function ContactForm() {
  const handleSubmit = () => {
    trackEvent('generate_lead', {
      form_name: 'contact_form',
      form_location: 'homepage'
    });
  };
}

4. Track Page Views (App Router)

// app/providers.tsx
'use client';

import { usePathname, useSearchParams } from 'next/navigation';
import { useEffect } from 'react';

export function AnalyticsProvider({ children }: { children: React.ReactNode }) {
  const pathname = usePathname();
  const searchParams = useSearchParams();

  useEffect(() => {
    if (pathname && window.gtag) {
      window.gtag('config', process.env.NEXT_PUBLIC_GA_ID!, {
        page_path: pathname + searchParams.toString(),
      });
    }
  }, [pathname, searchParams]);

  return <>{children}</>;
}

Custom Reports and Exploration

GA4's Exploration feature allows you to create custom reports that go beyond standard dashboards, providing deep insights into user behavior.

Popular Exploration Templates

Funnel Exploration

Visualize user drop-off at each step of key processes like checkout, sign-up, or onboarding. Identify where users abandon and optimize those steps.

Path Exploration

See the routes users take through your site. Discover common navigation patterns and unexpected user journeys.

User Lifetime

Analyze revenue and engagement over a user's lifetime. Critical for subscription businesses and SaaS products.

Creating Custom Dimensions

Custom dimensions let you add your own metadata to events for more detailed analysis:

Navigate to Admin → Data Display → Custom Definitions
Click Create Custom Dimension
Name your dimension and select the event parameter it maps to
Use in reports to segment data by your custom attributes

GDPR and Privacy Compliance

GA4 includes built-in privacy features, but you still need proper configuration to comply with GDPR, CCPA, and other privacy regulations.

Consent Mode Implementation

Google's Consent Mode allows GA4 to adjust its behavior based on user consent status:

// Set default consent state
gtag('consent', 'default', {
  'analytics_storage': 'denied',
  'ad_storage': 'denied'
});

// Update consent when user accepts
gtag('consent', 'update', {
  'analytics_storage': 'granted',
  'ad_storage': 'granted'
});

Privacy Settings in GA4

IP Anonymization: Enabled by default in GA4 (unlike Universal Analytics)
Data Retention: Configure how long user data is stored (2-14 months)
Signals: Control Google Signals for cross-device tracking
Data Deletion: Request deletion of specific user data via User-ID

Legal Requirement: Always implement a cookie consent banner and only enable analytics after receiving user consent. Consult with legal counsel for your specific jurisdiction.

Recommended Privacy Tools

Cookiebot: Comprehensive consent management platform with GA4 integration
OneTrust: Enterprise-grade privacy and consent management
CookieYes: Affordable GDPR/CCPA compliance solution for small businesses

Need Expert GA4 Implementation & Analysis?

Our analytics specialists will set up GA4 correctly, configure custom events and conversions, create tailored dashboards, and train your team—ensuring you get actionable insights from day one.

Explore Analytics Services Get Free Analytics Audit

Free GA4 audit • Custom dashboard setup • Team training included

Start Tracking What Matters

Google Analytics 4 is now the standard for web analytics, and understanding its event-based model is essential for making data-driven decisions. The shift from Universal Analytics wasn't just a rebrand—it's a fundamental change in how we measure and understand user behavior.

Start with the basics: enable enhanced measurement, set up your key events, and implement recommended events for your business model. As you become comfortable with GA4's interface, explore custom reports and advanced features like predictive metrics and audience building.

Most importantly, ensure your implementation is privacy-compliant from day one. The data you collect is only valuable if it's gathered ethically and legally. With proper setup and configuration, GA4 provides the insights you need to optimize your digital presence and grow your business in 2025 and beyond. For comprehensive digital marketing strategy that leverages analytics insights, explore our full range of digital marketing services.

Google Analytics 4 Complete Setup Guide: 2025 Best Practices

Key Takeaways

What is Google Analytics 4?

Key Differences from Universal Analytics

Setting Up GA4 Property

Step 1: Create GA4 Property

Step 2: Set Up Data Stream

Step 3: Install Tracking Code

Event Tracking Fundamentals

Event Categories

Tracking Custom Events

Configuring Key Events

How to Mark Events as Key Events

Common Key Events to Track

eCommerce Tracking Setup

Essential eCommerce Events

eCommerce Event Sequence

Next.js Integration Example

1. Create GA4 Script Component

2. Add to Root Layout

3. Track Custom Events

4. Track Page Views (App Router)

Custom Reports and Exploration

Popular Exploration Templates

Creating Custom Dimensions

Need Expert GA4 Implementation & Analysis?

Start Tracking What Matters

Related Articles

Key Takeaways

What is Google Analytics 4?

Key Differences from Universal Analytics

Setting Up GA4 Property

Step 1: Create GA4 Property

Step 2: Set Up Data Stream

Step 3: Install Tracking Code

Event Tracking Fundamentals

Event Categories

Tracking Custom Events

Configuring Key Events

How to Mark Events as Key Events

Common Key Events to Track

eCommerce Tracking Setup

Essential eCommerce Events

eCommerce Event Sequence

Next.js Integration Example

1. Create GA4 Script Component

2. Add to Root Layout

3. Track Custom Events

4. Track Page Views (App Router)

Custom Reports and Exploration

Popular Exploration Templates

Creating Custom Dimensions

GDPR and Privacy Compliance

Consent Mode Implementation

Privacy Settings in GA4

Recommended Privacy Tools

Need Expert GA4 Implementation & Analysis?

Start Tracking What Matters

What's the difference between GA4 and Universal Analytics?

Do I need to keep Universal Analytics and GA4 running together?

How do I migrate Universal Analytics goals to GA4 key events?

How long does it take for data to appear in GA4?

Can I track users across my website and mobile app with GA4?

Is GA4 GDPR compliant?

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