AI labs offer a range of models with different capabilities and prices, with costs varying further according to the version of a model and the “effort” settings used. Customers are typically charged for input tokens, used to measure data fed into a model, and output tokens, which measure what it generates in response.

The latest price cuts from US labs apply to mid-tier products and make them more competitive with Chinese offerings. OpenAI, for example, cut the price of GPT-5.6 Luna from $1 to $0.20 per million input tokens and from $6 to $1.20 per million output tokens.

Anthropic launched Opus 5 at $5 per million input tokens and $25 per million output tokens—half the price of its Fable 5 model. This week, the company called off a planned rise in prices for its Sonnet 5 model, which had been due to take effect from September.

Headline token prices do not provide a straightforward comparison between AI models, however. More capable models can sometimes complete a task using fewer tokens or with fewer attempts, meaning a model that appears more expensive based on the headline price of tokens can ultimately cost less.

Additionally, most can operate at different “effort” settings, which vary the computing power used to answer a question and can affect both performance and the ultimate cost of completing a task.

Artificial Analysis, which benchmarks models across areas including math, science, coding, and reasoning, found Anthropic’s Opus 5 at “medium” effort delivered similar performance and cost per task to Moonshot’s Kimi K3 at “max” effort. OpenAI’s GPT-5.6 Luna at “max” effort performed similarly to DeepSeek’s V4 Flash at “max,” but cost just under twice as much per task.

Anthropic and OpenAI declined to comment.

A person close to Anthropic said Opus 5’s pricing below its flagship Fable 5 was how the startup’s “family of models is built, so there’s no connection to competitors.”

Mantas Lukauskas, AI tech lead at Hostinger, a website hosting provider that has used large language models since 2020, noted that prices for the very best models were “flat to rising.”

He added that the recent pricing changes are the “first real test” of whether groups such as Anthropic and OpenAI can protect the cost of their most advanced offerings: “The US labs have cut the middle and are defending the top.”

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