E-Commerce Conversion Tracking | Measure Sales by Value
Measuring conversions in e-commerce is not just counting sales. The value of each sale has to be correct too, because the bidding strategy and the ROAS calculation rest on it. If the value is wrong, all optimisation pulls in the wrong direction.
Is the purchase event correct
The purchase event sits at the centre of measurement and must carry order ID, value, currency and product information. When one of these is missing, measurement appears to work while producing incomplete data.
The most common error I see is sending value including tax and shipping. That makes ROAS look better than it is and breaks the profit calculation. Which value you send is a choice, but it has to be consistent and you have to know what it includes.
Double counting in e-commerce
In setups tied to an order confirmation page, a user refreshing produces a second sale. Similarly, a user returning from a payment provider gets recorded twice in some builds.
Sending the order ID largely solves this: a second record arriving with the same ID is not counted again. In setups that do not send an order ID, double counting is nearly inevitable.
The payment provider trap
If the user goes to another site to pay and comes back, GA4 can treat that as a new session and record the sale with its source lost. The sale that advertising produced then shows up as direct traffic.
The fix is adding the payment provider’s domain to the referral exclusion list. That single setting corrects source attribution across many e-commerce accounts. I always check it during GA4 setup.
Returns and cancellations
This is the most skipped part of measurement. If returned orders stay recorded as conversions, high-return categories look more profitable than they are and the algorithm drifts toward them.
Feeding returns back brings measurement closer to reality. If automatic feedback cannot be built, applying the return rate to conversion value as an approximate correction also helps.
How do we start? First I test your purchase event: is the value right, is anything double counted, is the source being lost. I send the findings in priority order in writing. You can reach me from the contact page.
Frequently Asked Questions
Should conversion value reflect margin?
Ideally yes. Making the higher-margin of two equal-revenue products look more valuable to the algorithm pushes budget toward the profitable side.
Why does the GA4 sale count differ from my admin panel?
Some difference is normal — ad blockers, consent refusals and attribution differences all contribute. If the gap keeps widening there is a structural problem; comparing by order ID reveals the cause quickly.
Is the Shopify or WooCommerce plugin enough?
In most cases it sets up basic measurement, but default settings can produce double counting and incorrect values. Do not treat a setup as sufficient until it has been tested.
How do I work?
Work-hour packages
Tell me about your website and what you need on WhatsApp or by phone; we agree on a work block of somewhere between 5 and 40 hours and I start doing what is needed. What you get is not a calendar window — it is net working hours spent directly on your business. I can use 40 hours working three days straight, or deliberately spread it out and finish it over a year — whatever the work calls for. I do not spend my time estimating how long something will take, I spend it doing the work; every hour I spend has a lasting result on your site. We keep going for as long as you find it useful.
Why not monthly?
Is 40 hours a week?
On a fixed monthly fee both sides are watching the wrong thing: you watch a fixed cost, the other side watches how many more contracts like this they can line up. Working by the hour puts us both in front of the same thing — the real value of the work that got done. I know not having an upfront answer to "how much will this cost in total?" is the natural cost of this model. But instead of paying a fixed fee for months to a setup that is not producing results, you only pay for the qualified time spent on your work — and you see exactly where that time went, start to finish. That is why my clients keep coming back.