Google is enhancing Meridian, its open-source Marketing Mix Model (MMM), to help marketers make smarter, more precise budget decisions.

Why we care. Understanding ROI across channels is increasingly critical. These new Meridian updates allow for a more precise understanding of what drives sales, factoring in both media spend and non-media variables like pricing and promotions.

The big picture. Here’s what’s new:

  • Non-media variables: Marketers can now include pricing, promotions, and other business levers to measure their impact on sales more accurately.
  • Channel-level contribution priors: New features let you guide the MMM with your own business knowledge, improving the relevance of insights.
  • Longer-term effects: Enhanced binomial adstock decay functions track how upper-funnel media influences purchases weeks later.
  • Optimized spending: Marginal ROI (mROI) priors help pinpoint where the next dollar delivers the highest return, using past campaign performance.

Support and community. Meridian now has 30 certified global partners and an active Discord community, offering guidance to deploy the tool effectively and translate insights into business growth.

The bottom lineThese updates aim to transform Meridian from a measurement tool to a strategic partner for budget allocation. This means Meridian can help marketers optimize spend across immediate conversions and longer-term brand impact.


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Anu AdegbolaAnu Adegbola

Anu Adegbola has been Paid Media Editor of Search Engine Land since 2024. She covers paid search, paid social, retail media, video and more. In 2008, Anu’s career started with delivering digital marketing campaigns (mostly but not exclusively Paid Search) by building strategies, maximising ROI, automating repetitive processes and bringing efficiency from every part of marketing departments through inspiring leadership both on agency, client and marketing tech side. Outside editing Search Engine Land article she is the founder of PPC networking event – PPC Live and host of weekly podcast PPC Live The Podcast.
She is also an international speaker with some of the stages she has presented on being SMX (US, UK, Munich, Berlin), Friends of Search (Amsterdam, NL), brightonSEO, The Marketing Meetup, HeroConf (PPC Hero), SearchLove, BiddableWorld, SESLondon, PPC Chat Live, AdWorld Experience (Bologna, IT) and more.