The ChatGPT app.Didem Mente / Anadolu via Getty Images file

OpenAI announced it would begin rolling out test ads in ChatGPT Tuesday afternoon, affecting the free and Go tiers of the artificial intelligence chatbot service.

In a release announcing the beginning of ad testing on Tuesday, OpenAI said the ads will be clearly marked and "visually separated" from the chatbot`s answers. The ads will be "optimized based on what`s most helpful to you," the company wrote. The ads will be based on the user`s topic of conversation, prior chats, and previous interactions with ads.

OpenAI said the ads would not influence the chatbot`s replies, and that users will have the choice to prevent OpenAI from offering personalized ads based on user interests.

OpenAI has been teasing the introduction of ads for weeks. In a post on X in mid-January, OpenAI CEO Sam Altman announced the company would start testing ads but stressed "we will not accept money to influence the answer ChatGPT gives you and we keep your conversations private from advertisers."

OpenAI said it will "build protections to reduce the risk of scams and other harmful or misleading ads" and that it will not display ads for users under the age of 18, as determined by OpenAI`s predictions or the user`s own data.

OpenAI introduced ChatGPT`s Go tier in January. The Go tier costs $8 a month and gives users increased access to file uploads, image creation, and messaging compared to the Free tier.

While OpenAI competitor Google has also recently indicated that its AI platforms will feature ads in 2026, OpenAI rival Anthropic has declared that it will avoid placing ads in its Claude chatbot service for now.

In a blog post announcing the decision to forego ads last Wednesday, Anthropic wrote that "including ads in conversations with Claude would be incompatible" with positioning Claude as "a genuinely helpful assistant for work and for deep thinking."

Anthropic pilloried its rivals` allowance of ads in a new campaign of video ads, one of which played during the Super Bowl.

OpenAI`s Altman replied to Anthropic`s video ads with a caustic, lengthy rebuttal, labelling Anthropic`s messaging as "clearly dishonest." Altman said "we believe everyone deserves to use AI and are committed to free access," positioning OpenAI`s embrace of ads as a means to subsidize increased access to AI.