Making Sense of Google Meridian

By Hector I. Ariza, Senior Manager, Digital Marketing & Analytics, True Interactive

As consumers constantly scroll, stream, and shop across multiple platforms, advertisers face a daunting challenge: how do you measure the true impact of your marketing efforts? Google believes it has an answer: Meridian, an open-source marketing mix model (MMM) designed to give advertisers a way to analyze campaign impact using modern data science and real-world inputs. Meridian, launched in 2024, has expanded globally in 2025. Is Meridian right for you?

Why Google Created Meridian

One of the major challenges advertisers have been up against in recent years is that traditional measurement tools have become less effective amid the decline of third-party cookies. At the same time, digital campaigns have become more complex with the rise of AI-powered ads and performance media like search ads. Google created Meridian to address these issues. Google believes Meridian accounts for the intricacies of the advertising landscape while respecting user privacy.

Most traditional MMMs were built around static media environments and struggle to accurately account for performance campaigns or the interplay between digital and offline activity. That can lead to gaps in understanding and inefficient budget allocation. Meridian was developed to provide:

• Cross-channel measurement that incorporates search, social, video, and offline channels.
• Privacy-centered design that doesn’t depend on cookies or user-level data.
• Support for incrementality by integrating results from experiments and conversion lift studies.
• Code-level customization, allowing businesses to tailor models to fit their data structures and business logic.

The goal is to help advertisers align measurement with actual business outcomes.

Who Uses Google Meridian?

Meridian is used by marketers, data scientists, and media agencies seeking a customized, statistical approach to performance measurement. It supports efforts across both online and offline channels, whether a brand is investing in search ads, linear TV, or multi-platform campaigns.

To support a broader set of users, Google has partnered with over 20 certified measurement agencies. These partners offer expertise in setting up and applying the model. Finder, an Australian financial company, was an early adopter. Its marketing team reported that Meridian helped the company better understand the contribution of YouTube campaigns, beyond what standard conversion tracking could show. 

How Google Meridian Differs from Other MMMs

Meridian is designed to help advertisers evaluate the impact of their marketing efforts across digital and offline channels. Meridian uses advanced statistical methodologies, most notably Bayesian causal inference, to analyze historical data and deliver actionable insights into campaign performance. Here are some of the ways Meridian stands apart: 

Bayesian Probabilistic Forecasting

Unlike traditional MMMs that rely on regression-based analysis and provide single-point estimates, Meridian employs Bayesian causal inference to model uncertainty. This approach generates probability distributions rather than rigid predictions, allowing advertisers to assess a range of possible outcomes with confidence intervals. This is particularly valuable in dynamic marketing environments where consumer behavior and external factors are unpredictable.

Geo-Based Hierarchical Modeling

Meridian offers geo-level hierarchical modeling, enabling marketers to analyze campaign performance across different geographic locations. This feature is especially useful for brands targeting diverse markets, as it allows for localized insights rather than relying solely on national averages. For example, a campaign that performs well in urban areas may require adjustments for rural markets (a capability traditional MMMs often lack).

Integration with Google’s Ecosystem

Meridian is deeply integrated with Google’s platforms, including Google Ads, YouTube, and Google Analytics. This connection streamlines data ingestion and attribution for campaigns running on Google’s ecosystem. While this integration is a major advantage for brands heavily invested in Google platforms, it may be less effective for campaigns reliant on non-Google channels like TikTok or Amazon Ads.

Open-Source Customization

As an open-source tool, Meridian allows marketers to customize its framework to fit their unique business needs. Users can modify code and model parameters, incorporate proprietary datasets, and adjust Bayesian priors based on past knowledge or industry benchmarks. This flexibility makes Meridian more adaptable than closed MMM solutions like Meta Robyn or Orbit.

What Advertisers Might Gain from Meridian

According to Google, Meridian offers several advantages:

• Granular insights. Meridian delivers insights ranging from video ad metrics like reach and frequency to search campaign data such as query volume.
• Privacy-first approach. Meridian is built for a cookieless future.
• Predictive modeling. Meridian allows advertisers to test different budget scenarios before committing resources.
• Open-source flexibility. Businesses can customize the framework to fit their specific needs.

These features may be particularly valuable to advertisers looking for alternatives to closed MMMs or out-of-the-box attribution tools.

Potential Drawbacks

Meridian is a work in progress. It’s important to be aware of potential limitations:

• Google-centric focus. While potentially effective for campaigns on Google platforms like YouTube or Search Ads, it may be less useful for non-Google channels like TikTok.
• Learning curve. Advanced features require expertise in Bayesian statistics, a challenge for teams without strong analytics capabilities.
• Not real-time. It analyzes historical data rather than providing instant feedback.
• Data requirements. To get accurate results, businesses need at least two years’ worth of marketing spend and sales data.

Advertisers evaluating Meridian should weigh whether their teams have the technical skills and data maturity needed to implement and sustain a custom MMM.

How to Approach Meridian Strategically

If you’re thinking about adopting Google Meridian, here’s how you can set yourself up for success:

• Assess your data readiness. Ensure you have sufficient historical data before diving in.
• Partner wisely. Use one of Google’s certified agencies (including True Interactive) if your team lacks technical expertise.
• Experiment strategically. Test budget allocations across multiple channels using predictive modeling tools.
• Supplement as needed for brands relying heavily on non-Google platforms like TikTok or TV ads.

Succeeding with Meridian requires more than just using the tool. It means applying its insights across your entire advertising strategy. True Interactive can help you succeed with Meridian. Contact us here to learn how.