Overview
Claude Haiku 5.5, released in October 2026, brings adaptive thinking, a 1M-token context window and 128K output tokens to Anthropic’s smallest tier. Pricing is tiered by prompt length, with a lower rate for prompts up to 100,000 tokens.
Highlights
- 1M-token context window
- Up to 128K output tokens
- Adaptive thinking with medium effort by default
- Tiered pricing by prompt length
- Text and image input
Typical uses
Classification, extraction, routing, subagents and real-time applications.
Things to consider
- Its tokenizer counts about 30% more tokens than Claude Haiku 4.5 for the same text.
- Omit temperature, top_p and top_k.
Specifications are taken from the provider’s official announcement, documentation or model card. Benchmark results depend on evaluation settings; see how AI benchmarks work.