Anthropic ships Claude Haiku 5.5 at a quarter of Haiku 4.5's running cost, cuts Sonnet 5.5 cache reads
Anthropic released Claude Haiku 5.5, a small model it says runs at roughly a quarter of Haiku 4.5's cost for most prompts, and halved cache-read prices on Claude Sonnet 5.5 as it competes with OpenAI's GPT-6 Luna.
Haiku 5.5 arrives two weeks after Opus 5.5 launched on Sept. 22 and makes three models in the 5.5 generation. The company is aiming the new model at repetitive work, with high-volume summaries and classification as the main targets. Coding teams can also use it as a subagent to which Opus 5.5 or Sonnet 5.5 hands smaller tasks. Anthropic says no model of its own runs faster at standard speed, and suggests Haiku 5.5 for live customer support and browser automation.
The running-cost figure rests on a steep cut to list prices. Haiku 4.5, released last October, costs $1 per million input tokens and $5 per million output. For prompts of up to 100,000 tokens, which Anthropic says covered about 90% of the older model's requests, Haiku 5.5 is 90% cheaper on input and output alike, at 10 cents and 50 cents per million tokens. Longer prompts get a 50% discount. The 75% average saving the company quotes takes in a new tokenizer that uses slightly more tokens per task. Cost can be tuned further, because Haiku 5.5 is the first Haiku model with an adjustable effort setting.
The 10-cent and 50-cent rates match what OpenAI Group PBC charges for GPT-6 Luna, the low-cost model it launched last month. Anthropic's published benchmarks have Haiku 5.5 ahead of Luna on all six tests where both have a score. On OSWorld 2.1, which tests agents operating a real computer through long multistep tasks, the new model scored 72.4% on the offline subset against 48.9% for Luna. Luna scored 16.4% on the Terminal-Bench 4.0 agentic coding test, less than half the new model's 39.2%. For complex agentic coding, Anthropic still points customers to Sonnet 5.5 and Opus 5.5.
Asana Inc. was among the customers that tested Haiku 5.5 before release, running it through the evaluation suite for its AI Teammates agent. Task completion latency came in more than 30% lower than with the model Asana uses today, and inference on each agent turn ran up to 2.5 times faster. "It's a noticeably snappier experience," said Aaron Vinh, a staff software engineer at the company.
On safety, Anthropic said alignment testing turned up far fewer instances of misaligned behavior than Haiku 4.5 showed. Cybersecurity safeguards on the model allow more defensive work than Sonnet 5.5 permits. Penetration testing is still blocked, as are other techniques attackers are more likely to use, and organizations that need wider access can apply to the Cyber Verification Program Anthropic expanded on Tuesday.
The Haiku launch also came with a price cut for Anthropic's midsize model. Cache reads on Sonnet 5.5, which launched Sept. 28, drop from 20 cents per million tokens to 10 cents. Because cached tokens account for a large share of what models consume, Anthropic expects the cut to take about 20% off the cost of most agentic work on the model.
Claude Max and Team subscribers will also start receiving monthly application programming interface credits for the Claude Platform this week. A Max 5x subscription comes with $100 a month, double that on Max 20x. Team accounts get up to $500 shared across their users, and the credits can go toward any Claude model.
Haiku 5.5 is available now on the Claude Platform as claude-haiku-5-5 and through Amazon Web Services Inc., Google Cloud and Microsoft Azure.