Google Analytics Content Group, do I use gtag set or gtag config?

Question

I am trying to separate my site pages using "content group" in google analytics. So that I track how different page titles perform. I don't know which of these two is the right way to modify html code to track each group.

Do I use what I see under admin > property > view > content grouping ?

gtag('set', {'content_group1': 'My Group Name'});

OR what I see at https://support.google.com/analytics/answer/2853546?hl=en&utm_id=adcode

gtag('config', 'GA_TRACKING_ID', {'content_group1': 'My Group Name'});

Answer 1

Content group passed with set command will be added to the next hit, like:

gtag('set', {'content_group1': 'My Group Name'}); \\ No data sent

gtag('event', <action>, {                 \\ Now data will  include content group
  'event_category': <category>,
  'event_label': <label>,
  'value': <value>
});

Usually you'd want to have it sent with the first page view hit so gtag('config', 'GA_TRACKING_ID', {'content_group1': 'My Group Name'}); would work fine for you.