ChatGPT’s crawler GPTBot, which spiders the internet to capture information and turn it into knowledge, is the most-blocked bot on the internet, according to Cloudflare’s 2025 year in review. Meanwhile its biggest rival, Google, is the No. 1 most-allowed crawler. And perhaps even more interestingly, while ChatGPT is the most-blocked bot, it’s actually Anthropic’s Claude AI engine that is the least reciprocally beneficial service for website owners.