Anthropic launches the new version of the reduced model ‘Haiku’.

On Wednesday, Anthropic released the Claude Haiku 4.5, the newest version of its smaller model, billed as offering similar performance to the Sonnet 4 “at a third of the cost and more than twice the speed,” per the company. blog post.

Anthropic cites a number of new benchmark results to support these performance claims. In the company’s tests, Haiku scored 73% on SWE-Bench Verified and 41% on the command-line-focused Terminal-Bench — below Sonnet 4.5, but on par with Sonnet 4, GPT-5, and Gemini 2.5 in each case. Tests show similar results on benchmarks for tool use, computer use, and visual reasoning.

The new version of Haiku will be available immediately on all Anthropic free plans, and the company believes it will be particularly attractive for free versions of AI products, where it can provide significant capabilities by minimizing server loads. The lightweight nature of the model also means that it is easier to deploy multiple Haiku agents in parallel or in conjunction with a more sophisticated model.

In a statement to the press, Anthropic CPO Mike Krieger said Haiku will make new development styles possible in production for the first time. “It opens up whole new categories of what’s possible with AI in production environments – with Sonnet handling complex design while Haiku-powered sub-agents execute at speed,” said Krieger. “We give people a complete dealer toolkit where each model has the right combination of intelligence, speed and cost for different parts of the job.”

The most immediate applications are likely to come in software development tools, where Claude code is already widely used and latency is often a critical factor. In remarks provided by 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 releases for Anthropic: just two weeks after the release of Sonnet 4.5 and two months after the release of Opus 4.1both were hailed as state-of-the-art upon their release. The previous version of Haiku released in October 2024.