Have you ever run a Facebook ad to generate website visits? Did you notice a discrepancy between Facebook's reports and your own website tracking numbers?
It's not uncommon to see higher click numbers in your Facebook Ad Manager than your website tracking systems, like Google Analytics or Adobe's Site Catalyst.
Here are eight reasons why it can occur:
1. User is using HTTPS (hypertext transfer protocol secure) instead of HTTP (hypertext transfer protocol)
Communications through an HTTPS server are encrypted by a secure certificate known as an SSL, which prevents third-parties from eavesdropping on communications to and from the server. As a result, if your visitors are browsing Facebook via HTTPS, the analytics provider will under report conversions from Facebook ads. The difference between these protocols has been known to cause up to a 40% discrepancy in reporting, as reported by a Facebook representative.
2. User has an Ad Blocker or another content limitation plugin installed
If you're using a conversion pixel or a special tracking code appended to your link, it might not "fire" if the user has added an ad blocker to their browser. This will cause undercounting in conversions, and hence, a discrepancy in reports.
3. Firewall
The user or their server might have a firewall interfering with the reporting process.
4. URL shortener
If an advertiser uses a shortened link, some tracking systems might occasionally count redirects as "double clicks". Also, even though redirects typically load pretty fast, it might still slow down the overall user experience.
5. User closes out before the web page was able to load
If a user clicked on your ad by accident, or if it takes a while to load your page, most people typically lose patience and exit prematurely without seeing your content. Yet, Facebook will still count it as a click and will charge you for it.
6. JavaScript
JavaScript errors on your landing page or disabled JavaScript on a browser might cause undercounting as well.
7. User is browsing without saving data
Incognito window/browser settings that prevent from storing cookies will most likely result in lower click counts in your website tracking system.
8. Cookies versus session data
Facebook uses cookies while many website tracking platforms use session data. A click on a landing page linked to your Facebook ad sends a request to access the page and all of the user's cookies associated with the site. Cookies are saved on the user's end within user's browser.
Session data works similarly to cookies, but instead of everything being stored on the user side, it's stored on the server side. The only snippet of information stored on the user's end is the session ID. Because session data is not stored locally, tracking web page activity can be volatile.
Unfortunately, it's almost impossible to achieve perfect reporting, regardless of the tracking method used. The good news is that Facebook's looking for ways to make it a fair game for its advertisers - for example, every time a user clicks on a URL linked to your ad, Facebook automatically pulls that user's profile and removes duplicates and robots. Facebook also periodically monitors their network for spammer accounts and fake profiles.
Hopefully these few tips shed the light on why a discrepancy might occur in reports and what causes it.