Anthropic vs OpenAI: Claude maker's growth challenges ChatGPT ahead of IPO

Anthropic has filed for an initial public offering, reporting $16.29 billion in revenue for the first half of 2026, positioning itself as a strong challenger to OpenAI in the business AI market. The filing intensifies competition between the two companies as investors weigh their growth prospects. Anthropic's revenue surged to $4.59 billion in 2025 from $386 million in 2024, driven by demand for its Claude models, particularly coding tools. OpenAI reported $6.7 billion in quarterly revenue for Q2 2026, with an annualized run rate near $50 billion. However, accounting differences for cloud-partner sales complicate direct comparisons. Both companies face significant financial pressures, with Anthropic reporting a $693 million operating loss in H1 2026 and OpenAI expecting to use about $278 billion in cash through 2030. Anthropic relies heavily on Amazon and Google for infrastructure, while valuations in private markets have reached approximately $1.5 trillion for Anthropic and over $1.4 trillion for OpenAI.