The Ecomm Analyst

This question comes up almost every time I look at a new store’s stack. Google Analytics is already installed and it costs nothing, so why pay for a dedicated attribution tool on top of it? It is a fair thing to ask. The honest answer is that GA4 and ThoughtMetric are not really competing for the same job, and most of the frustration I see comes from asking one of them to do the other one’s work.

What GA4 is built to answer

GA4 is a behavioral web analytics platform. It is designed to tell you what people did on your site. Which landing pages pulled traffic, where sessions dropped off, how deep people got into the funnel, how organic search is trending once you connect Search Console. The standard tier is free with no volume commitment. The enterprise tier, Analytics 360, is sold through Google sales and priced by quote, which puts it well outside the range most stores I work with would consider.

For that behavioral job GA4 is good, and it is free. I keep it running on every store I touch.

What ThoughtMetric is built to answer

ThoughtMetric, which sponsors this blog, is an e-commerce attribution platform. It connects to Shopify for order data and to your ad accounts for spend, then reports revenue against spend down to the campaign and ad level. The question it exists to answer is which spend produced which orders. Pricing is $99 a month on pageview-based tiers starting at 50,000 pageviews, or $83 a month billed annually. Every feature is available on every tier, and the 14-day trial does not ask for a card.

The revenue mismatch that starts most of these conversations

Nearly every operator who asks me this question has already noticed that GA4’s revenue number does not match what Shopify reports. That gap is normal and it has structural causes. GA4 counts what its tag observes in the browser, which means consent banners, ad blockers, Safari’s cookie handling, and app-based checkouts all take a bite. Shopify counts orders it processed. Those are two different measurements, and no amount of configuration makes them converge fully.

An attribution tool built on order data starts from the Shopify side instead. It knows the order happened because Shopify says it happened, then works backward to figure out what touched that customer. That is a meaningfully different foundation, and it is the main reason the two tools produce different channel numbers.

Where GA4 is the better tool

On-site behavior is the obvious one. If you want to know which product page has a collapse in add-to-cart rate, or which blog post is quietly pulling organic traffic that converts, GA4 is where you go. It also feeds audiences straight into Google Ads, which matters if Google is a real channel for you. And the Explore interface, once you get past the learning curve, will build custom reports that most dedicated e-commerce tools do not try to compete with.

Where it falls short for spend decisions

GA4 does not know what you spent. Google Ads cost data flows in through the native link, but Meta, TikTok, and everything else do not, so ROAS by channel is not something GA4 can hand you without external work. Its default attribution is data-driven within a Google-shaped view of the world, which tends to read paid search generously. And there is no cost of goods anywhere in the product, so you cannot get from revenue to contribution without exporting.

Those are not defects. They are just the edges of what a general-purpose web analytics tool was designed to cover.

How I would actually decide

I would stop framing it as a choice. Nearly every store I work with runs GA4 for site behavior and something else for spend allocation, and that arrangement works fine. The failure mode is not paying for two tools. It is trying to run budget decisions out of GA4 and then spending two hours a week reconciling numbers that were never going to agree.

If you are still deciding whether the second tool earns its place, I wrote about that question directly in whether you still need GA4 once you have an attribution tool. The short version is that the two rarely cancel each other out.

One practical note before you switch anything. Attribution tools build their history from the point you connect them, so the reports get more useful the longer they run. That argues for starting the clock earlier rather than waiting until you have a budget question you need answered this week.