Anthropic launches new version of scaled-down ‘Haiku’ model

On Wednesday, Anthropic released Claude Haiku 4.5, the latest version of its smallest model, which is billed as offering similar performance to Sonnet 4 “at a third of the cost and more than twice as fast,” according to a company. blog post.

Anthropic cites a series of new benchmark results to support these performance claims. In the company’s testing, Haiku scored 73% on verified SWE-Bench and 41% on the command-line-oriented Terminal-Bench – lower than Sonnet 4.5, but comparable in both cases to Sonnet 4, GPT-5 and Gemini 2.5. Tests show similar results on benchmarks for tool use, computing and visual reasoning.

The new version of Haiku will be available immediately under all free Anthropic plans and the company believes it will be especially attractive for free versions of AI products, where it can deliver significant capabilities while minimizing server load. The lightweight nature of the model also means that it is easier to deploy multiple Haiku agents in parallel or in combination with a more advanced model.

In a statement to the press, Anthropic CPO Mike Krieger said the Haiku would enable new ways of deploying in production for the first time. “It opens up entirely new categories of what’s possible with AI in production environments – with Sonnet handling complex scheduling while Haiku-powered sub-agents execute quickly,” Krieger said. “We’re giving people a complete agent toolbox, with each model having the right combination of intelligence, speed and cost for different parts of the job.”

The most immediate applications will likely be in software development tools, where Claude Code is already widely used and latency is often a critical factor. In statements from Anthropic, Zencoder CEO Andrew Filev described the new version of Haiku as “unlocking a whole new set of use cases.”

Haiku 4.5 comes after a series of high-profile launches for Anthropic: just two weeks after the launch of Sonnet 4.5 and two months afterward the launch of Opus 4.1both of which were praised as state-of-the-art upon release. The previous version of Haiku was released in October 2024.