OpenAI's advertising business has reached an annualized revenue run rate of $1 billion, according to the company. OpenAI touts this as proof of its diversified business model.

The company is preparing for a major IPO and is under pressure to justify its $852 billion valuation. The roughly 200-day-old advertising business is meant to add to existing revenue streams like corporate customers, subscriptions, and usage-based APIs. OpenAI began testing ads in ChatGPT in the US in February.

ChatGPT ads are now available in more than 40 countries, and a self-serve option launches today in India, Europe, the Middle East, and North Africa. Ads show up for Go subscribers and free users. OpenAI says they're clearly labeled and aren't meant to influence its answers. Advertisers get no access to private conversations.