Hey! It’s Théo today. We’ll speak about the topic of tracking parameters in Google Ads, especially the ones that confuse even advanced marketers: GCLID, GBRAID, and WBRAID.

Since the rollout of Apple’s App Tracking Transparency (ATT), traditional tracking methods have lost their precision. But Google didn’t give up. They adapted. And if you’re running Paid Ads, understanding the difference between these three parameters can help you better attribute conversions, even in a privacy-first world.


Let’s dive into the logic behind these identifiers, how they work, and what they mean for your campaigns as Google Ads expert.

What Is GCLID in Google Ads?

GCLID stands for Google Click Identifier. It’s the original tracking parameter that Google uses to connect a specific ad click to a conversion.

Every time someone clicks on a Google ad, this unique ID is appended to the URL. It allows Google Ads and Google Analytics to tie the click to a keyword, audience, or campaign that drove it. This is the foundation of conversion attribution in the pre-iOS 14 era.

You’ll typically see GCLID in:

  • Desktop traffic
  • Android users
  • iOS users who opt in to tracking (rare)


But here’s the issue: GCLID relies on user-level data, which Apple’s iOS privacy framework now restricts. So on iOS devices, GCLID often gets stripped or blocked.


Why Did Google Introduce GBRAID and WBRAID?

To stay compliant with Apple’s privacy rules, Google introduced two new identifiers: GBRAID and WBRAID. Unlike GCLID, they don’t rely on user-level identifiers. Instead, they use aggregated data that respects user privacy.

On the left, each click tied to its own conversion, as with GCLID; on the right, on iOS, GBRAID and WBRAID link a group of clicks to a group of conversions using aggregated data.

This change allows Google to keep measuring performance and optimizing your campaigns even when personal identifiers can’t be used.


So if your traffic comes from iOS, you’re no longer tracking with GCLID but with one of these two new options depending on the journey.


What’s the Difference Between GBRAID and WBRAID?

Understanding the difference comes down to where the click starts and ends in the user journey.

IdentifierWhen it appliesWhat it ties to the click
GCLIDDesktop and Android, or iOS when the user opts in to trackingOne specific conversion, at user level
GBRAIDiOS, web to app: the click opens the app through a deep linkConversions in the app, as aggregated data
WBRAIDiOS, app to web: the click starts inside an iOS appConversions on the website, as aggregated data


GBRAID

Used for: Web-to-app tracking

Example: A user clicks a Google ad in Safari (web), a deep link opens your app, they convert in-app.

In this case, GBRAID enables attribution from the web click to the in-app conversion, even without tracking individuals.


WBRAID


Used for: App-to-web tracking

Example: A user clicks a Google ad inside an iOS app, they visit your website, they convert.

Here, WBRAID allows for attribution from the in-app click to the web conversion while remaining ATT compliant.

These identifiers work without personal data, which makes them acceptable under Apple’s privacy framework. They rely on aggregated event measurement rather than deterministic matching.


How Are GBRAID and WBRAID Privacy Compliant?

Apple’s ATT framework forces advertisers to stop tracking individuals across apps and websites. Google’s solution respects this by avoiding any individual identifiers.

Here’s how:

  • No personal user IDs are tracked
  • Conversion attribution is based on aggregated data
  • The signals are designed to optimize at the group level, not the user level


This makes both GBRAID and WBRAID compatible with Apple’s guidelines while still delivering campaign insights and optimization signals.


Why This Matters for Paid Search and Performance Campaigns

If you’re running Paid Advertising, especially across multiple devices or iOS users, here’s why understanding these parameters is key:

  • Without proper attribution, you undercount conversions
  • Underreporting leads to under-optimization
  • Campaigns can appear less profitable than they really are

Knowing whether your campaigns are using GCLID, GBRAID, or WBRAID helps you analyze performance more accurately and adjust your bidding strategy accordingly.

For example:

  • Use GBRAID to measure web clicks that end in a conversion inside an iOS app
  • Use WBRAID to attribute iOS in-app traffic going to a website
  • Use GCLID for everything else: Android, desktop, and opted-in iOS users


Key Takeaways

GCLID is the classic tracking ID used by Google Ads to follow clicks and measure conversions

Apple’s privacy rules forced Google to innovate. GBRAID and WBRAID were created in response

GBRAID = web to app (click on web, conversion in app)

WBRAID = app to web (click inside an app, conversion on web)

Both are aggregated, privacy compliant, and allow for campaign-level optimization even without user-level tracking