OpenAI’s annualised revenue for September was almost $50 billion, about $20 billion below the nearly $70 billion figure reported by several media outlets late last month, the Financial Times reported on Thursday, citing financial documents shared with investors.
The discrepancy mainly arose from an attempt to produce a direct comparison with figures from rival Anthropic.
OpenAI vs Anthropic: Why the revenue figures differ
The two companies calculate their annualised revenue differently. Anthropic includes revenue from sales through cloud partners such as Amazon Web Services (AWS) and Google Cloud, while OpenAI does not, according to the FT report.
The difference complicates efforts by investors to compare the financial performance of the two AI companies, which are competing to sign up more business customers.
OpenAI, Anthropic IPO plans: What investors need to know
Both companies have filed confidential paperwork to go public. Anthropic could launch its initial public offering (IPO) as soon as this fall, while OpenAI has said it no longer expects to list this year as it focuses on addressing safety concerns surrounding its technology.
The potential listings could give Wall Street a clearer view of the companies’ finances, including the sustainability of their rapid growth amid the AI boom.
What is the annualised revenue run rate?
Annualised revenue run rate is a commonly used metric among fast-growing Silicon Valley startups. It often involves multiplying a company’s revenue in a single month by 12 to estimate how much it would generate over a year if that pace continued.
However, the metric can be misleading because it extrapolates current performance rather than measuring revenue earned over a full year. Differences in calculation methods can further complicate comparisons between companies.
OpenAI revenue growth: From $40 billion to $50 billion
OpenAI started this year with $20 billion in annualised revenue versus $6 billion in 2024. Its quarterly revenue was eclipsed by Anthropic for the first time in the second quarter, with OpenAI reporting $6.7 billion compared to Anthropic’s $11.5 billion.
Anthropic’s annualised revenue crossed $65 billion in July and is set to reach $100 billion by year-end, sources previously told Reuters.
OpenAI has seen sales accelerate as businesses adopt its newer AI models and coding tools, intensifying its competition with Anthropic for corporate customers.
As both companies move towards potential public listings, investors will need to look beyond headline revenue run rates to understand how their businesses generate sales and whether their growth can be sustained.