Adding another data point here: I had a very good post here on HN in the last year (about 1600 upvotes), and this was the only place where I shared it or saw i

Adding another data point here: I had a very good post here on HN in the last year (about 1600 upvotes), and this was the only place where I shared it or saw it posted. I know a few people discussed it on Twitter, too, so a good fraction of my traffic was likely "sourced from Twitter" by these metrics. Per Cloudflare, I had about 180k visitors during the 2-day period when that blog post was on the front page here, and another 60k during the following week. I don't have any trackers on the blog so I don't know the traffic sources or any other more granular breakdown. At the time, my baseline was about 400 visitors a day, which I attribute to RSS feeds and bots. I know that Cloudflare overestimates unique visitors, since it is just using layer 3-4 factors, but I'm not sure it overestimates by that large of a factor. I would assume that the HN impact for his post was likely underestimated thanks to secondary sharing effects. A lot of links go from HN to Twitter, Reddit, and other communities, where they get second chances at "going viral."