What AI slowdown? OpenAI, Anthropic release dueling models as price wars heat up

Anthropic and OpenAI debuted more affordable versions of their frontier models as they battle for wallet share from increasingly cost-conscious businesses, and face growing competition from lower cost open weight models.

The releases came within hours of each other, a sign of the labs’ heated rivalry, despite both companies’ recent calls for an AI slowdown .

Anthropic debuted Claude Opus 5.5, which it says performs at the level of its flagship Fable 5.1 model but costs around 40% less to run than Opus 5 , which came out in July.

It’s the first release in a new family of models, with Sonnet 5.5 and Haiku 5.5 expected “over the coming weeks,” Anthropic said.

Anthropic said the model is its most efficient, and it’s “passing these efficiency savings on to our customers in the form of price cuts and rate limit increases.” OpenAI released GPT-6 Sol and GPT-6 Luna, offshoots of its flagship GPT-6 Astra model that came out earlier this month.

The idea is to offer a version of Astra for everyday work, OpenAI said.

It also slashed the API cost by 50% lower than the pricing on a promotion it’s currently running for Astra’s predecessor, GPT-5.6.

OpenAI often releases lower priced versions of its flagship models, as it did with GPT-5.6.

OpenAI’s release offers lower API pricing than Anthropic’s, based on each company’s announcement , as shown in the table below.

OpenAI attributes the cost reductions to “improvements in caching and inference,” and, like Anthropic, says it’s also “passing those savings directly onto users and customers.” The two labs are already deep into an all-out price war—something that could put pressure on their ability to profit from their models down the line.

“OpenAI and Anthropic are engaged in a price war that is driving down the price of AI and therefore driving down their ability to profit from it and grow the price of models,” Ara Kharazian, lead economist at Ramp, told Fortune .

The battle is playing out on two fronts, Kharazian said: the labs are rolling out cheaper models that businesses are shifting toward, such as Opus 5.5 and GPT-6 Sol and Luna, while also announcing outright price cuts on their most expensive ones.

That dynamic is how technology markets have traditionally worked, he said, but it’s something that more bullish investors may not be factoring in.

“AI bulls assume that there will be highly performant models that provide more and more value, and therefore they should be more expensive,” Kharazian said.