Claude Haiku 5.5 API

Q: What is the Claude Haiku 5.5 model ID?

Use anthropic/claude-haiku-5.5 as the model parameter. Requests go to the OpenAI-compatible endpoint with your AI/ML API key.

Try this model

Claude Haiku 5.5 is Anthropic's fastest current model, built for high-volume, latency-sensitive work such as classification, extraction and routing, with a 1M-token context window.

Modalities: Text, ImageText
In / Out price: $0.1/$0.5per 1M
Context window: 1M tokens
Released: Oct 7, 2026

Claude Haiku 5.5 overview

Claude Haiku 5.5 specs

Model ID: anthropic/claude-haiku-5.5
Developer: Anthropic
Context window: 1,000,000 tokens
Max output: 128,000 tokens
Input: Text, Image
Output: Text
API: OpenAI-compatible, base URL https://api.aimlapi.com/v1

What Is Claude Haiku 5.5 API?

Claude Haiku 5.5 is the fastest model in Anthropic's current lineup. Anthropic positions it for high-volume, latency-sensitive tasks such as classification, extraction and routing, and gives it the same 1M-token context window and 128K maximum output as Opus 5.5 and Sonnet 5.5 at a fraction of their price.

It uses the same tokenizer as Claude 4.7 and later, so the same text counts as roughly 30% more tokens than on Claude Haiku 4.5.

Technical Reference

Developer	Anthropic
Model ID	anthropic/claude-haiku-5.5
Release Date	October 7, 2026
Context Window	1,000,000 tokens
Max Output Tokens	128,000 tokens
Modalities	Image, Text → Text
Thinking	Adaptive, default effort medium
Knowledge cutoff	June 2026
Capabilities	Vision; tool use; multilingual; prompt caching

What Claude Haiku 5.5 Brings to the Table

Fastest in the lineup
Anthropic rates its comparative latency as the fastest of the four current models, ahead of Sonnet 5.5.

Adaptive thinking
The model decides how much to think, steered by the effort parameter, which defaults to medium here. Omit temperature, top_p and top_k, a non-default value for any of them returns a 400 error.

Cheap cache reads
Prompt cache reads cost 10% of the base input price, which matters when the same context is sent on every request.

Vendor-Reported Benchmarks

Published by Anthropic with the Claude Haiku 5.5 announcement, retrieved 7 October 2026. These are the vendor's own figures and have not been independently reproduced.

OSWorld 2.1: 72.4% (offline subset)
Humanity's Last Exam: 45.9% without tools, 57.4% with tools

Where Claude Haiku 5.5 Makes the Most Sense

Work measured in millions of calls
Classification, routing and extraction, where the price per request decides whether the pipeline is viable.

Interfaces people wait on
Suggestions and inline assistance, where the fastest model in the family is the point.

Triage before escalation
Haiku handles the volume and hands the hard cases to Opus or Sonnet.

Sources: https://www.anthropic.com/claude-haiku-5-5 · https://platform.claude.com/docs/en/models/haiku-5-5/overview

Use cases

Classification and routing: the work Anthropic names first, deciding what a request is and where it goes, at volume.
Extraction: pulling structured fields out of documents, tickets and screenshots.
Latency-sensitive interfaces: autocomplete, inline suggestions and anything a person waits on.
High-volume pipelines: the cheapest model in the current Claude lineup, which decides what is affordable to run on every record.
Long-document triage: a 1M-token window on a model priced for bulk work.

Capabilities

Function calling
Streaming
Structured outputs
Reasoning
Web search

Claude Haiku 5.5 benchmarks by Artificial Analysis

See how Claude Haiku 5.5 compares in intelligence, generation speed and cost per task. Data retrieved Nov 3, 2026.

Intelligence#14 / 5036.2Index v5.0 Speed#19 / 219235Output tokens / second Cost per task#13 / 44$0.41USD / benchmark task Humanity's Last Exam#27 / 45844.4%Score

Intelligence

Index v5.0

Speed

Output tokens / second

Cost per task

USD / benchmark task

Benchmark results

Compare 5 models available on AI/ML API across 4 independent benchmarks.

Humanity's Last Exam

Expert-written questions across academic subjects.

Claude Haiku 5.5 API pricing

Claude Haiku 5.5 pricing in US dollars
Usage	Price	Unit
Input	$0.1	1M tokens
Output	$0.5	1M tokens
Cached input	$0.01	1M tokens

Prices from the AI/ML API price list, checked on Nov 4, 2026.

Claude Haiku 5.5 vs other models: token prices

AI/ML API input and output rates for 5 models, per million tokens.

AI/ML API model prices in USD per million tokens
Model	Input	Output
Claude Haiku 5.5	$0.1	$0.5
Claude Sonnet 5.5	$2	$10
Claude Opus 5.5	$4	$20
Claude Opus 5	$5	$25
Claude Fable 5.1	$10	$50

How to use the Claude Haiku 5.5 API

View docs

Build with your agent

Give your agent the model details, code and documentation.

1Get your API key

Create API key

export AIMLAPI_KEY="8f2b4c7d9a1e6b3f…"

2Make your first request

curl 'https://api.aimlapi.com/v1/chat/completions' \
  -H "Authorization: Bearer $AIMLAPI_KEY" \
  -H 'Content-Type: application/json' \
  -d '{
  "model": "anthropic/claude-haiku-5.5",
  "messages": [
    {
      "role": "user",
      "content": "Write a haiku about the ocean."
    }
  ]
}'

import os
import requests

headers = {
    "Authorization": f"Bearer {os.environ['AIMLAPI_KEY']}",
    "Content-Type": "application/json",
}
payload = {
    "model": "anthropic/claude-haiku-5.5",
    "messages": [
        {
            "role": "user",
            "content": "Write a haiku about the ocean."
        }
    ]
}

response = requests.post("https://api.aimlapi.com/v1/chat/completions", headers=headers, json=payload, timeout=120)
response.raise_for_status()
print(response.json())

const response = await fetch("https://api.aimlapi.com/v1/chat/completions", {
  method: "POST",
  headers: {
    Authorization: `Bearer ${process.env.AIMLAPI_KEY}`,
    "Content-Type": "application/json",
  },
  body: JSON.stringify({
    "model": "anthropic/claude-haiku-5.5",
    "messages": [
      {
        "role": "user",
        "content": "Write a haiku about the ocean."
      }
    ]
  }),
});

if (!response.ok) throw new Error(`HTTP ${response.status}`);
console.log(await response.json());

All posts

Claude Haiku 5.5 FAQ

What is Claude Haiku 5.5?

Claude Haiku 5.5 is Anthropic's fastest current model. Anthropic positions it for high-volume, latency-sensitive tasks such as classification, extraction and routing, and lists it as the fastest in the current lineup.

How much does Claude Haiku 5.5 cost?

Claude Haiku 5.5 costs $0.1 input and $0.5 output per 1M tokens on AI/ML API, billed as you go with no subscription.

How large is the Claude Haiku 5.5 context window?

1M tokens, with a maximum output of 128K tokens on the synchronous endpoint. Anthropic notes that batch requests can reach 300K output tokens with a beta header.

Does Claude Haiku 5.5 support extended thinking?

It uses adaptive thinking: the model decides how much to think, steered by the effort parameter. The default effort on Haiku 5.5 is medium.

Can Claude Haiku 5.5 read images?

Yes. Anthropic states that all current Claude models support text and image input, text output, multilingual capabilities, vision and tool use.

What is the Claude Haiku 5.5 model ID?

Use anthropic/claude-haiku-5.5 as the model parameter. Requests go to the OpenAI-compatible endpoint with your AI/ML API key.

Start building with Claude Haiku 5.5

Get API key

Claude Haiku 5.5 API

anthropic/claude-haiku-5.5

Build with your agent

Give your agent the model details, code and documentation.

1Get your API key

Create API key

export AIMLAPI_KEY="8f2b4c7d9a1e6b3f…"

2Make your first request

curl 'https://api.aimlapi.com/v1/chat/completions' \
  -H "Authorization: Bearer $AIMLAPI_KEY" \
  -H 'Content-Type: application/json' \
  -d '{
  "model": "anthropic/claude-haiku-5.5",
  "messages": [
    {
      "role": "user",
      "content": "Write a haiku about the ocean."
    }
  ]
}'

import os
import requests

headers = {
    "Authorization": f"Bearer {os.environ['AIMLAPI_KEY']}",
    "Content-Type": "application/json",
}
payload = {
    "model": "anthropic/claude-haiku-5.5",
    "messages": [
        {
            "role": "user",
            "content": "Write a haiku about the ocean."
        }
    ]
}

response = requests.post("https://api.aimlapi.com/v1/chat/completions", headers=headers, json=payload, timeout=120)
response.raise_for_status()
print(response.json())

const response = await fetch("https://api.aimlapi.com/v1/chat/completions", {
  method: "POST",
  headers: {
    Authorization: `Bearer ${process.env.AIMLAPI_KEY}`,
    "Content-Type": "application/json",
  },
  body: JSON.stringify({
    "model": "anthropic/claude-haiku-5.5",
    "messages": [
      {
        "role": "user",
        "content": "Write a haiku about the ocean."
      }
    ]
  }),
});

if (!response.ok) throw new Error(`HTTP ${response.status}`);
console.log(await response.json());

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Claude Haiku 5.5 API

Claude Haiku 5.5 overview

Claude Haiku 5.5 specs

What Is Claude Haiku 5.5 API?

Technical Reference

What Claude Haiku 5.5 Brings to the Table

Vendor-Reported Benchmarks

Where Claude Haiku 5.5 Makes the Most Sense

Use cases

Capabilities

Claude Haiku 5.5 benchmarks by Artificial Analysis

Intelligence

Speed

Cost per task

Benchmark results

Humanity's Last Exam

Terminal-Bench 4.0

AA-LCR

SciCode

Claude Haiku 5.5 API pricing

Claude Haiku 5.5 vs other models: token prices

How to use the Claude Haiku 5.5 API

Build with your agent

1Get your API key

2Make your first request

Related articles

Claude Haiku 5.5 FAQ

Start building with Claude Haiku 5.5

Claude Haiku 5.5 API

Build with your agent

1Get your API key

2Make your first request

Claude Haiku 5.5 API

Claude Haiku 5.5 overview

Claude Haiku 5.5 specs

What Is Claude Haiku 5.5 API?

Technical Reference

What Claude Haiku 5.5 Brings to the Table

Vendor-Reported Benchmarks

Where Claude Haiku 5.5 Makes the Most Sense

Use cases

Capabilities

Intelligence

Speed

Cost per task

Benchmark results

Humanity's Last Exam

Terminal-Bench 4.0

AA-LCR

SciCode

Claude Haiku 5.5 API pricing

Claude Haiku 5.5 vs other models: token prices

How to use the Claude Haiku 5.5 API

Build with your agent

1Get your API key

2Make your first request

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