Why are Google Ads reporting different numbers than Google Analytics?

Google Ads and Google Analytics handle the same data very differently. And for good reason.

When you’re dealing with multiple sessions (meaning a website visitor came to the site more than once before converting) the conversion data can be displayed in multiple ways. This is called “attribution modeling.”

Google Ads and Google Analytics tend to use different attribution models because their purpose is different: Google Ads is trying to show us which ads are profitable, when, why, etc. Google Analytics, on the other hand, is trying to show us the most straightforward picture of what exactly happened on the site and when.

So, the two platforms almost always end up attributing conversions based on different rules:

  • Google Analytics uses a same-day attribution model. This means the day that the conversion happens is the day that Google Analytics will show the data.
  • Google Ads uses one of several different attribution models (whichever one your ad manager chose in the account settings) to analyze the performance of the ads. So, if someone clicked on an ad a month ago, but then converted today, some or all of today's conversion will appear a month in the past.

In addition to this, the two platforms have different levels of tracking capabilities to recognize the same user across different channels, devices, etc:

  • Google Analytics measures session date using browser cookies. This is all it needs, since it's only looking at data that happens within a single session.
  • Google Ads measures session data using browser cookie, too, but also by IP address, session ID, and even WiFi. It also can recognize Google users if people are logged in on their phone or their Chrome browser and connect the dots that way.

Keep this in mind when using Google Analytics: It is a tool that has been developed to show you what's going on on your website. It only sees where users came from immediately before converting, which means it's direct traffic will be high since many people who interact with a paid ad will come back to the site directly when they're ready to convert.