Anthropic releases Claude Haiku 5.5 for fast, high-volume work

Anthropic released Claude Haiku 5.5 on October 7, 2026. The model ID is claude-haiku-5-5; Anthropic positions it for high-volume, latency-sensitive work such as classification, routing, extraction, summaries, compactions, and database queries. The company also recommends it as a subagent alongside Opus 5.5 or Sonnet 5.5 for coding work. (https://www.anthropic.com/claude-haiku-5-5; https://platform.claude.com/docs/en/models/haiku-5-5/overview)

Adaptive effort and model limits

Haiku 5.5 supports adaptive thinking controlled by the effort parameter. Anthropic’s API documentation lists a 1 million-token context window and up to 128,000 output tokens. The page describes adaptive thinking as on by default and lists medium as the default effort. The same text produces about 30% more tokens than with Haiku 4.5 because Haiku 5.5 uses a newer tokenizer, so teams should test their own prompt and cost profiles before migrating.

Anthropic’s published pricing is $0.10 per million input tokens and $0.50 per million output tokens for prompts up to 100,000 tokens; prompts over that length are listed at $0.50 input and $2.50 output per million. The company says the model costs around 75% less to run on average than Haiku 4.5, a comparison based on its stated workload mix rather than a guarantee for each request. (https://www.anthropic.com/claude-haiku-5-5; https://platform.claude.com/docs/en/models/haiku-5-5/overview)

Availability

Anthropic lists the model as active on the Claude API, Amazon Bedrock, Google Cloud, Microsoft Foundry, and Claude Platform on AWS. Its release notes also say Haiku 5.5 is available in Claude Code. Cursor separately announced it in its model picker on October 7; see our Cursor Haiku 5.5 update. (https://platform.claude.com/docs/en/models/haiku-5-5/overview; https://support.claude.com/en/articles/12138966-release-notes; https://x.com/ClaudeDevs/status/2107895955144208813)

Sources

• Anthropic — “Introducing Claude Haiku 5.5” (October 7, 2026): https://www.anthropic.com/claude-haiku-5-5
• Claude Platform Docs — Claude Haiku 5.5 model overview: https://platform.claude.com/docs/en/models/haiku-5-5/overview
• Claude Help Center — October 7, 2026 release notes: https://support.claude.com/en/articles/12138966-release-notes
• ClaudeDevs on X — Haiku 5.5 availability (October 7, 2026): https://x.com/ClaudeDevs/status/2107895955144208813