Exceptional spike in traffic: can Google Analytics help to know the reason?

Question

Imagine your traffic is like this, with a spike that is 2 times higher than usual average values (sometimes it can be x3 or x10):

In order to find the reason, of course you can manually go to Acquisition > All traffic > Channels, and then trying Referral, Direct, Social, (Other), Organic search to see if the spike is still there in one of them.

But this is not very handy.

Is there a clever tool in Google Analytics to guess the reason for a traffic spike?

Answer 1

There is a method to do this in Google Analytics, here's what you need to do -

1. Change your date range to the date where you have the spike only
2. Compare this range (1 day) to the previous period (last day)
3. Then move to the Acquisition Section -> Sources/Medium report in Google Analytics
4. You should see source/medium wise figures on which source has suddenly given you an increase in traffic
5. If it is Referral traffic, then most likely a popular site has linked to you. If that's the case, then in the Secondary Dimension option, select Referral Path
6. Now you can add the source/medium + the referral path to get to the page which is talking about you/linking to you

Answer 2

Google Analytics hides the ability to compare various metrics on one graph under the feature it calls "motion charts". You access motion charts using the three dot icon on the top right of the graph.

Once in motion charts, make sure the metric you want is shown on the graph. In this case you want it to be "Sessions".

You also need to put the motion chart into line graph mode using the tab that appears on the top of the graph.

Once you have the graph in this mode, you can easily see which metric spiked during that time period. You can just mouse over the graph to and information about the line you are hovering over will appear.