Sudden jump in bounce rate for no apparent reason?

When you refer to Google Optimize, you are talking about Google's own service, https://www.google.com/analytics/optimize/, or you are talking about something else out there?

If it is Google's service, what were you testing? Were you doing A/B testing of different pages? Does discontinuing the service stop the A/B delivery of pages? I'm not sure.

Also, it could just be a coincidence that this started when you started using Google Optimize.

Where are the bounces coming from? Organic search, paid ads, Facebook traffic, etc?

I have seen cases in the past where a webpage started ranking for a high volume keyword that was similar to what they were targeting, but wasn't really relevant to their page.

It was like the difference between someone searching for "styles of dogs" and "doggie style". The words are similar, but they mean two completely different things.

So if the bounces are just from traffic that is not relevant, it's not really a big deal.

You need to dig into the traffic a little more.

This sounds very strange.

My first reaction is that 3% bounce rate wasn't real in the first place - it's WAY too low - I don't think I've ever seen a bounce rate as low as that.

85% I have seen - it's quite high - you'd certainly want to improve it if possible - but it sounds more real than 3% - so I wonder if there was something configured wrong before, rather than now.

Here are a few things I'd look at:

Did your A/B test change all your pages? What range of bounce rates are you seeing on different pages? Have they all changed at the same time?

How do bounce rates from different traffic sources compare?

How have your pageviews per session changed? What about Average Session Duration?

How has your time on page changed?

If this is a real change in bounce rate, I'd expect to see big changes in these other metrics too.

Assuming you're using Google Analytics, I think I'd try installing another analytics program as well - such as Piwik - to double check what's going on.

Hope that helps.

Now obviously, I haven't seen the site myself, but perhaps it is possible that the split testing script has increased the loading time, which is causing people to leave? Also, if you are split testing, have you made sure the tracking is in both versions of the page?

What about your conversions? Have they changed?

If the site is still converting at the same rate, I would guess the 3% bounce rate wasn't real like someone mentioned above.

A high bounce rate is not always a bad thing by the way, but a change like that is odd.

Proper way of reading a bounce should be like this, 20% below is really bad while 70% onward is also a bad signal, 26 to 40% is excellent, 41 to 55% is average.

Thank you for all the replies.

I fear you are right MikeFriedman. I did find two copies of the analytics code. One in the header, one in the footer (and one in the backend, but that didn't seem to be doing anything).

I'm almost certain it's now correct as I removed every bit of code I could find and checked by sending test traffic in analytics. It didn't record the activity. Pop the code in the header and it works again. This would indicate there is only copy of the analytics code.

I also had to educate myself on bounce rate. I always thought it was someone who came on the site and left immediately, but I understand it's just where they haven't had a second interaction (never left the entry page).

I've restarted the Google Optimise. Interestingly (we are a video production company), when I remove examples from the home page, we get the bounce rate down to 45%. The highest is with the most examples on the home page (75% bounce).

I guess the measures we're interested into discount things like load time (which bounce rate does bugger all in helping you to define if this is the reason visitors are bouncing off), is the time on site and number of pages visited.