Welcome to the Q&A Forum

Google search console Index Status report Google Webmaster tools tell you in the https://support.google.com/webmasters/answer/2642366?hl=en if you want to know without a doubt you have to connect Google Analytics to Deepcrawl it will say exactly how many URLs are in the index. https://www.deepcrawl.com https://www.deepcrawl.com/knowledge/best-practice/how-to-measure-indexed-pages-more-accurately/ https://www.deepcrawl.com/knowledge/best-practice/how-can-non-indexable-pages-receive-google-organic-traffic/ http://www.stateofdigital.com/40-deepcrawl-tweaks/ Now that Google Analytics can be added to screaming frog you can do something very similar. https://www.screamingfrog.co.uk/seo-spider/ https://www.screamingfrog.co.uk/seo-spider/user-guide/general/#crawling https://www.screamingfrog.co.uk/seo-spider/faq/ https://moz.com/community/q/how-to-determine-which-pages-are-not-indexed I Hope this helps, Tom