The paper discusses the thesis of extended belief and its implications for the possibility of extending ordinary, personal level knowledge. A common worry is that knowledge will overextend, that there will be ‘cognitive bloat’. If the subject’s standing beliefs can be realized in devices such as notebooks and smart phones, what is there to prevent the conclusion that she knows everything stored on such devices? One response to this worry is to block the move from belief to knowledge, and argue that these externally stored beliefs, although reliable, do not qualify as knowledge. I argue, instead, that the fundamental problem arises at the level of belief. We prevent bloating of knowledge by preventing the bloating of belief. To do so, I argue, we need to take seriously Clark and Chalmers’ suggestion that what is distinctive of belief is its role in folk psychological explanations. Paying attention to this role shows that the usual examples, such as Otto’s notebook information, do not qualify as beliefs. To qualify, the external information would have to be much more directly connected to, and deeply integrated into, the subject’s overall system of beliefs and desires.