What is Referral Spam and How to Recognize it in Google Analytics

A few weeks ago, one of my clients noticed a spike in referral traffic in Google Analytics. Naturally, he was excited, thinking that his website was gaining popularity, with people linking to it and visitors coming in. Unfortunately, that wasn’t the case.

You don’t need to be a Google Analytics expert to see that all the traffic my client was excited about was actually referral spam. Referral spam is used as a lead generation technique or as a way to drive traffic to shady websites and earn affiliate commissions. In this article, you’ll learn how referral spam works and how to recognize it in your Google Analytics account.

Types of Referral Spam

Referral spam is coming to Google Analytics in two different forms:

• Traffic from spammy web crawlers.
• Ghost referral traffic.

There are many spammy websites that use bots (web crawlers) to crawl the web and index webpage data.
Most respectable web crawlers identify themselves as such to web servers and therefore they are excluded from Google Analytics reports.
The spammy web crawlers, however, don’t identify themselves as robots. In that way, the websites that sent the spammy crawler to end up in your Google Analytics referrals report and trick you into visiting them (or visiting other spammy websites to which they redirect).

If you open one of these fake referral URLs (not recommended), you will probably be redirected to an online store, online marketing scam, or a porn site. The owner of the fake referral website receives a commission if you purchase something from the website he’s redirecting to.

Here’s an infographic that explains how referral spam is used in affiliate marketing:

Other websites are using referral spam as a lead generation technique. They use crawlers to produce entries in your Google Analytics site’s referral list and trick you into visiting them.

The other type of referral spam in GA is called ghost referral traffic.
Ghost referral spam doesn’t even visit your website. It is generated by simple programs that send fake HTTP requests to multiple Google Analytics properties. These fake HTTP requests are translated as fake hits and sessions in your GA reports. The automated script that sends the fake HTTP requests can set the referrer to be any URL.

So basically, once the spammer has your Google Analytics property ID, he can promote any website by generating page views in Google Analytics without sending requests to the actual web site.

Below you’ll find a list of domains that are known to be produced using ghost referrals:

• simple-share-buttons.com
• darodar.com
• hulfingtonpost.com
• humanorightswatch.org
• ilovevitaly.com
• o-o-6-o-o.com
• priceg.com
• s.click.aliexpress.com
• blackhatworth.com

How to recognize referral spam in Google Analytics

The fake referral traffic is not difficult to recognize in GA reports. It typically has several of the following characteristics:

• Bounce Rate of 0% or 100%
• Avg. session duration of 0s
• % New Sessions of 0%
• Landing Page is /

But “typically” doesn’t mean “always”. For all four criteria I mentioned, you could also see counter-examples, such as the following:

Almost all of the referral sessions of this website are coming from fake referrals. We see that most of the visits have a 100% bounce rate and 0s session duration.

The first website, however (floating-share-buttons.com) is also notorious referral spam but it has a bounce rate of 87.29% and 57s session duration.
That’s an example that the metrics bounce rate, average session time and % new sessions are not always the most reliable signals to recognize referral spam.

Another way to recognize referral spam in Google Analytics is by checking if :

• the fake referrals are reported with fake or (not set) hostnames or
• the fake referrals have fake page titles

If we take the example of above and we add Hostname as the secondary dimension, we can clearly see that 5 of the referral websites have real hostnames:

Normally, as secondary dimension, you should see the hostnames under which your Web site is reachable. But in the screenshot above, most of the hostnames are either “not set” or fake.
Most probably the type of referral spam we’re dealing with here is ghost referral spam. But unfortunately, it’s difficult to know for sure…

And a third way to recognize fake referral traffic is by simply visiting the referrer site.
In most of the cases, you will land on a referring page that doesn’t have your backlink or you’ll be redirected to another domain.

Impact of fake referrals to your Google Analytics account

The big problem with fake referral traffic is that it’s skewing your website statistics.

It’s especially annoying on new websites, that don’t receive a lot of referral traffic yet. Let’s see an example of a new website affected by referral spam:

This website has received 421 visits (sessions) from referrals during the selected date range. Unfortunately, all of these “sessions” are sent from fake referrals. As a result all avg. behavior metrics for referral traffic are not accurate.

Moreover, in the case of a new and unpopular website, fake referral traffic could quickly become the main acquisition channel:

In the eyes of an inexperienced website owner, this report says that the most effective acquisition channel is a referral (which is not true).

The website avg. session duration, avg. pages/session per view and bounce rate are also inaccurate because they are heavily impacted by the metrics from the fake referral sessions.

And there’s more: spam traffic does not convert on any of your goals, therefor the conversion rate will be also impacted.

As a result, referral spam traffic not only inflates your session count, it also dilutes some of your key performance metrics, such as engagement and your conversion rate.

In summary, if your website is heavily impacted by spam referral traffic, your Google Analytics data is not trustworthy.

Many important marketing decisions are based on web analytics data, and inaccurate data can lead to poor business decisions and a false perception of your website’s performance.

FAQ on Referral Spam

1. What is referral spam?

Referral spam is fake traffic recorded in Google Analytics, generated by bots or programs that send fake HTTP requests, making it appear as if your website is receiving legitimate referrals.

2. How can I detect referral spam?

Look for unusual metrics like 0% or 100% bounce rates, check hostnames, and manually verify suspicious referrers.

3. Can referral spam harm my website?

While it doesn’t harm your website directly, it skews your analytics data, leading to poor decision-making.

4. How does referral spam affect my website’s analytics?

Referral spam skews your analytics data, inflating session counts and diluting key performance metrics such as bounce rate, session duration, and conversion rate, leading to inaccurate insights and poor business decisions.

5. How can I recognize referral spam in Google Analytics?

Referral spam can be recognized by its characteristics: 0% or 100% bounce rate, 0 seconds session duration, and fake or (not set) hostnames. Additionally, visiting the referrer site can confirm its authenticity.

6. What are ghost referrals?

Ghost referrals are a type of referral spam that does not visit your website but sends fake HTTP requests to your Google Analytics property, generating fake hits and sessions.

7. How can I prevent referral spam in Google Analytics?

To prevent referral spam, use filters in Google Analytics to exclude known spammy domains, set up valid hostnames filters, and use referral exclusion lists to block fake traffic sources.

8. Is ghost referral traffic preventable?

While it’s difficult to prevent entirely, setting up filters and monitoring your analytics regularly can minimize its impact.