Depending on the type of website you are working with, it is likely that some percentage of your users are using their browser in incognito or private mode.

Since using incognito mode can skew the numbers you see in analytics, it is really good to know the estimated percentage of visitors that prefer to stay incognito.

What kind of implications does incognito mode cause?

Inaccurate user count – every session is a new user

– every session is a new user Inaccurate sessions per user count – incognito users will always have only one session

– incognito users will always have only one session Broken A/B testing logic – users in incognito are likely to see different variation every time they visit

– users in incognito are likely to see different variation every time they visit Broken promotions – users are likely to see “only once” popups and other elements in every session

Tracking incognito users in Google Analytics

Unfortunately, browsers don’t have a default solution for detecting whether users are in incognito or not. Nor are they making it easy to figure it out using custom Javascript.

For every browser, the solution is a bit different and they might be changing when a new version of the browser is released. We are doing our best to keep this post up to date.

Here’s the Google Tag Manager setup that we are using to track incognito visitors to Reflective Data blog.

Google Tag Manager custom HTML tag

Name: Detect Incognito Browser

Type: Custom HTML

Trigger: All Pages

Code: