Claude Haiku 3.5
Anthropic's fast and affordable model. Great for quick tasks, summarization, and simple coding.
Claude Haiku 3.5 is text & chat AI model from Anthropic, priced at €8.00 per 1M input tokens with a 200K tokens context window.
0.7
Examples
See what Claude Haiku 3.5 can generate
Classify the sentiment of this review: 'The food was decent but the service was painfully slow. Waited 45 minutes for appetizers.'
Sentiment: Mixed/Negative. The review acknowledges acceptable food quality ('decent') but expresses clear frustration with service speed. The word 'painfully' and the specific wait time of 45 minutes indicate the negative experience with service outweighed the neutral food assessment. Overall lean: negative.
Translate 'Where is the nearest train station?' into French, Spanish, and Japanese
French: 'Où est la gare la plus proche ?' Spanish: '¿Dónde está la estación de tren más cercana?' Japanese: '最寄りの駅はどこですか？' (Moyori no eki wa doko desu ka?)
Pricing
API Integration
Use our OpenAI-compatible API to integrate Claude Haiku 3.5 into your application.
npm install railwailimport railwail from "railwail";
const rw = railwail("YOUR_API_KEY");
// Simple — just pass a string
const reply = await rw.run("claude-haiku-3-5", "Hello! What can you do?");
console.log(reply);
// With message history
const reply2 = await rw.run("claude-haiku-3-5", [
{ role: "system", content: "You are a helpful assistant." },
{ role: "user", content: "Explain quantum computing simply." },
]);
console.log(reply2);
// Full response with usage info
const res = await rw.chat("claude-haiku-3-5", [
{ role: "user", content: "Hello!" },
], { temperature: 0.7, max_tokens: 500 });
console.log(res.choices[0].message.content);
console.log(res.usage);Deep dive — Anthropic's Claude Haiku 3.5
Anthropic was founded in 2021 by Dario Amodei (CEO), Daniela Amodei (President) and a group of ex-OpenAI researchers. The company operates as a Public Benefit Corporation with a stated mission to build reliable, interpretable and steerable AI systems. Anthropic's research output includes 'Constitutional AI' (2022), 'Scaling Laws for Neural Language Models' (2020), interpretability work on Sparse Autoencoders and Toy Models of Superposition, and the Responsible Scaling Policy that defined ASL safety levels. The Claude product line launched in March 2023 and now spans the Haiku (small/fast), Sonnet (balanced) and Opus (frontier) tiers across multiple generations. Claude 3.5 Haiku was released in late 2024 as the speed-optimised entry tier of the 3.5 family. Investors include Google, Amazon, Spark Capital and Lightspeed, with total disclosed funding exceeding $15 billion. Anthropic is one of the most influential frontier-lab brands and a key participant in industry safety commitments with the US AISI and UK AISI institutes.
Visit Anthropic →Claude 3.5 Haiku is the lightweight, fast tier of the Claude 3.5 family, designed for low-latency and high-throughput workloads where Sonnet-level capability would be cost-prohibitive. Architecturally it is a decoder-only Transformer trained on a similar curated corpus to the larger Claude models, including web text, books, source code and licensed datasets, with a knowledge cutoff in mid-2024. Compared to Claude 3 Haiku, Anthropic reports that 3.5 Haiku outperforms the previous flagship Claude 3 Opus on many benchmarks while keeping the cost profile of a small model, achieved through improved data mixture, better post-training and architecture refinements. Post-training combines supervised fine-tuning, RLHF and Constitutional AI critiques. The model supports tool use, JSON mode, vision input and structured output but does not expose an extended thinking mode (that ships in Claude 3.7 and 4). Haiku 3.5 is heavily optimised for inference throughput, often running 2-3x faster than Sonnet on the same hardware, making it suitable for real-time customer-facing applications and high-volume data pipelines. Anthropic published a model card detailing safety evaluations and behavioural changes versus the previous Haiku generation.
- Parameters
- Undisclosed (estimated low tens of billions, dense)
- Context
- 200K tokens
- Sub-second time-to-first-token for short prompts
- Strong instruction following at small model size
- 200K context window for long-document tasks
- Vision support for images, charts and PDFs
- Tool use and structured JSON output
- High throughput suitable for real-time chat workloads
- Outperforms Claude 3 Opus on several reasoning and code benchmarks despite smaller size
- Multilingual coverage of major world languages
- Constitutional-AI tuned for safe, helpful responses
- Cheap enough for use as a router/classifier in agent stacks
- Best for: high-volume chat, classification, summarisation, light coding tasks.
Trained on Anthropic's curated mixture of web, books, code and licensed data, with a knowledge cutoff around July 2024. Post-training uses RLHF plus Constitutional AI critiques on a much smaller human-rated set.
License: Proprietary commercial license via Anthropic API, Amazon Bedrock and Google Vertex AI.
Known limitations
- Weaker than Sonnet/Opus on hard reasoning and competition math
- No extended thinking mode
- Knowledge cutoff July 2024
- Will refuse certain dual-use queries
- No customer fine-tuning available
Frequently asked questions
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