OpenAI and Anthropic share the same roots: Anthropic’s founding team came from OpenAI, yet the two companies took opposite paths. Remember it in one line: OpenAI wants to be AI for everyone, while Anthropic wants to be the AI enterprises trust most.
To meet each one on its own, read What is OpenAI? and What is Anthropic?.
Positioning: mass-market consumers vs enterprise first
OpenAI’s home turf is the public. More than 1.2 billion people use ChatGPT each week (official figure, October 7, 2026). On top of that it stacks enterprise subscriptions, an API, images, and voice. The goal: become the place where you can ask anything.
Anthropic leans toward enterprises. Its products center on text, code, and enterprise workflows. Businesses and developers drive its growth, and AI safety is the core of its brand.
Product matchups: two direct contests
- ChatGPT vs Claude: ChatGPT has the broadest feature set, with images, voice, and search. Claude focuses on text, coding, and long documents. As of October 2026, the two companies’ top models are GPT-6 Astra and Claude Fable 5.1.
- Codex vs Claude Code: A head-to-head contest in AI coding. Codex integrates with the ChatGPT platform and is easy to pick up. Claude Code is good at understanding large codebases and has been one of Anthropic’s fastest-growing engines in recent years.
Revenue: counted differently, so don’t compare directly
Both companies describe their growth with ARR (annualized revenue: recent revenue projected over a full year, which is not the same as cash actually received):
| OpenAI | Anthropic | |
|---|---|---|
| ARR | About US$50 billion (end of September 2026, according to Axios) | Officially more than US$47 billion (May 2026); according to Bloomberg, more than US$65 billion at the end of July |
The difference is how revenue sold through cloud partners is counted. Anthropic counts the full amount sold through partners such as Amazon and Google; OpenAI counts only its own share. According to Axios, investors who recalculated OpenAI’s number the Anthropic way got close to US$70 billion. So the table only shows the rough scale; it can’t tell you which is bigger.
Valuation and IPOs: both are lining up to go public
Based on each company’s latest private round as of October 2026, Anthropic’s post-money valuation of about US$965 billion (May 2026) is higher than OpenAI’s roughly US$852 billion (March 2026). Both are prices set by private investors, not public stock prices.
As of October 2026, both companies have confidentially submitted draft S-1 filings to the SEC. Neither has published financial statements or a listing date:
- Anthropic: According to a Bloomberg report in early October, it could start its formal roadshow as soon as the week of November 9, aiming to list before Thanksgiving (November 26) and by year-end at the latest. The timeline may still change.
- OpenAI: CEO Sam Altman said in a September 2026 interview that OpenAI will not go public in 2026, and he did not commit to 2027 either.
For details, read How much is OpenAI worth? and The complete guide to an Anthropic IPO.
Compute: building an empire vs borrowing from many clouds
OpenAI is building its own. Its core is Stargate, a data center joint venture built with SoftBank, Oracle, and MGX. It is also designing its own inference chip, Jalapeño, with Broadcom. Read more in What is Stargate?.
Anthropic plugs into the big clouds. Its compute comes from Amazon, Google and Broadcom, and Microsoft and NVIDIA. It also rents GPUs at SpaceX’s Colossus data center. Using many suppliers spreads the risk. The tradeoff: key investors such as Amazon and Google are also its compute suppliers.
Safety: a calling card vs a source of controversy
Anthropic treats safety as a competitive advantage. Its 2026 Responsible Scaling Policy moved to a safety roadmap, risk reports, and external review; the roadmap’s goals are not hard commitments.
OpenAI’s flagship GPT-6 Astra is its first widely deployed model to reach the “Critical” level for cybersecurity capability. Its safety practices also keep drawing scrutiny: in September 2026, the California Attorney General formally opened an investigation into OpenAI’s Hugging Face security incident. For the internal disputes, read OpenAI’s leadership team; for lawsuits and investigations, read OpenAI’s legal battles.
Penchan’s summary
The two companies started from the same place but gave two different answers to how AI should be built. OpenAI is betting on breadth and scale: get the whole world using it first, then make money. Anthropic is betting on trust and focus, believing enterprises will pay for AI that is safer and better at getting work done.
Once they list, their public financial statements will let outsiders measure them with the same ruler for the first time. Until then, each leads on its own battlefield, and there will be no single winner.