What is the AI compute crunch, and why are AI tools hitting usage limits?

In late March some of the heaviest users of Anthropic’s Claude large language models began posting screenshots of a strange new scarcity: they were reaching five-hour usage limits in 20 minutes. Complaints spread across Reddit, GitHub and X. Anthropic told subscribers that their sessions would burn through usage limits faster during peak hours. The company also blocked some third-party tools, including OpenClaw, from drawing on its flat-rate subscription limits. Several weeks earlier Boris Cherny, who leads Claude Code, said that a default setting for how the model thinks had been lowered.Users immediately questioned why a paid AI tool was suddenly giving them less. Had the AI boom begun to outrun the machinery needed to sustain it?The pressure is not limited to Anthropic. OpenAI has begun shuttering Sora, its video-generation platform, as the number of developers using its coding assistant Codex has surged to four million per week. Investors and developers are now talking about a “compute crunch,” the possibility that demand for AI is growing faster than companies can build data centers and power them.On supporting science journalismIf you're enjoying this article, consider supporting our award-winning journalism by subscribing. By purchasing a subscription you are helping to ensure the future