Major artificial intelligence platforms ChatGPT, Claude and Grok experienced widespread service disruptions on Thursday, September 3, leaving users in different parts of the world unable to access some of their most-used AI tools.

The disruptions began at roughly the same time, with outage reports rising sharply on Downdetector. ChatGPT appeared to be the hardest hit, with tens of thousands of users reporting problems, while Claude and Grok also recorded significant spikes.

OpenAI confirmed that ChatGPT and Codex were experiencing elevated error rates, affecting multiple functions, including conversations, logins, file uploads, search, voice mode, image generation and Deep Research. The company later said it had applied a mitigation and was monitoring recovery.

Anthropic's Claude was similarly affected, with the company reporting elevated errors across several models and later identifying an infrastructure issue behind the disruption. Claude.ai, Claude Code and its API were among the affected services.

Meanwhile, Grok, operated by xAI, also experienced service problems across its web and mobile platforms, with users encountering messages indicating that the model was overloaded.

The simultaneous outages attracted particular attention because the three services are operated by separate companies. While Microsoft Azure was also experiencing outage reports and provides cloud infrastructure used by the affected AI companies, there was no confirmation that the incidents were caused by a common problem.

The disruption also highlighted the growing dependence on AI services for work, research, programming, communication and other everyday tasks. When major AI platforms experience downtime, the effects can extend beyond individual users to businesses and applications that rely on their APIs.

Services began recovering for some users later Thursday, although the companies continued monitoring their systems as the situation developed