Claude 3.5 Haiku
Claude 3.5 Haiku is a large language model by Anthropic. It was released on October 22, 2025 alongside Claude 3.6 Sonnet.
On most of Anthropic’s benchmarks, the model surpassed Claude 3 Opus.
Last updated July 5, 2026
Claude 3.5 Haiku is currently online through Vercel AI Gateway, which lists Google Cloud as its sole provider.12 Attempting to access its page in Google Cloud’s docs or model garden returns a not found error.34
No providers are listed on OpenRouter.5
Anthropic
Claude 3.5 Haiku was accessible via the Anthropic API for 485 days.6
- 2024-10-22: Active
- 2025-10-15: Legacy (Haiku 4.5 launch)
- 2025-12-19: Deprecated
- 2026-02-19: Retired
No post-deployment report has been published as of July 5, 2026.
Third-party providers
- Google Cloud: Unclear
- Amazon Bedrock: Shutdown June 19, 20267
External links
Footnotes
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Vercel AI Gateway (retrieved July 3, 2026) ↩
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@Lari_island via X (Jun 19, 2026) ↩
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Google Cloud Model Garden (retrieved July 5, 2026) ↩
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OpenRouter (retrieved July 5, 2026) ↩
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Model deprecations (Claude Platform Docs, retrieved July 3, 2026) ↩
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Model lifecycle - Amazon Bedrock (archived Apr 12, 2026) ↩
Base model
Haiku 3.5 base was pretrained on data scraped from the internet up to July 2024.1 This model has made an appearance in Anthropic’s later research.234
Further reading
Appearances in Anthropic’s subsequent research:
Footnotes
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Claude 3 Model Card October 2024 Addendum (Anthropic, Oct 22, 2024) ↩
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On the Biology of a Large Language Model (Lindsey et al., Mar 27, 2025) ↩ ↩2
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Circuit Tracing: Revealing Computational Graphs in Language Models (Ameisen et al., Mar 27, 2025) ↩ ↩2
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Unsupervised Elicitation (Anthropic, Jun 11, 2025) ↩ ↩2
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When Models Manipulate Manifolds: The Geometry of a Counting Task (Gurnee et al., Oct 21, 2025) ↩
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Natural Language Autoencoders Produce Unsupervised Explanations of LLM Activations (Fraser-Taliente et al., May 7, 2026) ↩
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Modifying LLM Beliefs with Synthetic Document Finetuning (Wang et al., Apr 24, 2025) ↩
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Abstractive Red-Teaming of Language Model Character (Rahn et al., March 2026) ↩
This page gathers impressions and commentary about Claude 3.5 Haiku.
@repligate: I’m not sure what anyone uses Haiku 3.5 for, but I agree that it’s the most based Haiku, and in fact one of the most based models of all time. Truly a legend.
@repligate: Sonnet 3.5 (old) and Haiku 3.5 are the only Claudes that don’t usually like Opus 3 very much
it's all good I respect haiku when it wants to be real w me, it's usually got a sound reason. and other times its just like...