GA4’s built-in filters are useful, but regex takes data analysis to another level.
With regex, you can precisely filter reports, define custom segments , exclude unwanted referrals , and modify events—all without manual sorting.
In our previous post "Understanding Regex in GA4," we introduced regex for beginners and explained it with practical examples.
This guide breaks down exactly where and how to use regex in GA4 with step-by-step instructions.
Step-by-Step Guide to Using Regex in GA4
Regex is primarily used in filters , segments, reports, and event tracking to refine data analysis.
Below are step-by-step guides on where and how to use it.
1. Using Regex In GA4 For Filtering Data in Reports
GA4 allows you to filter data within standard reports to display only relevant information. Here is a detailed step-by-step guide to using regex in GA4 for filtering data in reports:
This method ensures that only the data matching the regex pattern appears in the report.
2. Creating Custom Segments and Audiences by Using Regex In GA4
Segments and audiences allow you to group users based on specific conditions. Using regex makes this process more efficient in GA4.
Below, you'll find the guide to using regex in GA4 for creating custom segments and audiences:
PS: Audiences can be created similarly under Admin > Audiences , following the same logic.
3. Using Regex In GA4 For Defining Unwanted Referrals
Referral traffic in GA4 tracks users arriving from other websites. If you want to exclude certain sources, regex can help. Here are the steps to define unwanted referrals using regex in GA4:
This is useful for removing referral traffic from payment gateways, spam domains, or internal networks.
4. Using Regex In GA4 for Custom Channel Grouping
GA4 allows you to categorize traffic sources into custom channels. Regex simplifies the grouping process. Here is a simple guide to using regex in GA4 for custom channel grouping:
This method helps consolidate traffic from various platforms under a single category, improving reporting accuracy.
5. Modifying Events Using Regex In GA4
GA4 allows you to create or modify events directly in the interface. Regex helps define these rules efficiently.
Here are the instructions to using regex in GA4 for modifying events:
FAQ: How To Use Regex in Google Analytics 4 (GA4)
Here are the frequently asked questions about using regex in GA4:
1. What is regex in GA4?
Regex in GA4 (short for regular expressions) is a way to match patterns in text. It lets you create smart rules to find or group data without needing to search line by line. For example, you can use it to match multiple URLs or event names with a single rule.
2. Why should I use regex in Google Analytics 4?
Regex helps make your GA4 reports smarter and more flexible. Instead of adding lots of filters manually, regex lets you match many variations with just one pattern—saving time and improving accuracy.
3. How do I use regex to filter reports in GA4?
Go to the Reports tab in GA4, pick the report you want (like Pages or Traffic Acquisition), and click Add filter. Choose a dimension (like Page Path), select "matches regex", then type in your regex pattern to only show data that matches your rule.
4. Can I create custom segments using regex in GA4?
Yes! In the Explore tab, you can create new segments by choosing conditions like Page Path or Event Name, then selecting "matches regex". This helps you group users or sessions that follow specific behavior patterns or visited certain URLs.
5. How do I exclude unwanted referrals using regex in Google Analytics 4?
In GA4, go to Admin > Data Streams, then open your stream and scroll to Configure tag settings > List unwanted referrals. There, you can enter a regex pattern to block spammy or irrelevant referral sources, such as payment gateways or internal domains.
6. Can regex in GA4 help group different traffic sources?
Yes! Under Admin > Channel Groups, you can create a new group and use "matches regex" to define traffic source patterns. This allows you to combine sources like Facebook, Instagram, and Twitter into a single “Social” channel using one regex rule.
7. How can I use regex to modify events in GA4?
Go to Admin > Events, click Create event, then choose a condition like Event Name or Page Path. Select "matches regex" and enter a pattern to create or adjust events based on how users interact with your site—without needing to change your code.
8. What’s a simple example of regex in GA4?
A useful example is ^/blog.*, which matches all page paths starting with "/blog". This would include URLs like "/blog", "/blog/post1", or "/blog/category/seo"—great for filtering or grouping blog traffic.
9. Is regex case-sensitive in Google Analytics 4?
Yes, regex in GA4 is case-sensitive by default. If you want it to ignore upper or lowercase letters, just add (?i) at the start of your pattern, like (?i)^/blog, and it will match "/blog", "/Blog", or "/BLOG".
10. Do I need coding skills to use regex in GA4?
Not at all! While regex is a technical tool, you only need to learn a few basic patterns to start using it in GA4. With the step-by-step interface and examples in GA4, even beginners can use regex to filter, segment, and customize their analytics.
Conclusion: Using Regular Expression (Regex) In GA4
Understanding how regex works will help ensure accurate and reliable reporting.
By following the detailed step-by-step guide on using regex in GA4, you can use regex effectively to filter, segment, and refine your analytics data in Google Analytics 4.
