Claude Haiku 4
Anthropic Claude 4 Generally Available Oct 2025
Anthropic's fastest and most affordable Claude 4 model. Matches Sonnet on coding benchmarks at 3× lower cost and 2× the speed — ideal for real-time and agent workloads.
Context
200K
tokens
Input
$1.00
per MTok
Output
$5.00
per MTok
Modalities
Input
Text Vision Documents / PDFs Code
Output
Text Code
Code Examples
curl https://api.anthropic.com/v1/messages \
-H "x-api-key: $ANTHROPIC_API_KEY" \
-H "anthropic-version: 2023-06-01" \
-H "Content-Type: application/json" \
-d '{
"model": "claude-haiku-4-20251001",
"max_tokens": 1024,
"messages": [
{ "role": "user", "content": "Explain quantum entanglement in one sentence." }
]
}' API Parameters
| Name | Type | Description |
|---|---|---|
frequency_penalty | number | Penalize tokens by their frequency so far. Positive values reduce repetition. |
max_completion_tokens | integer | Maximum number of tokens the model may generate in the response. |
presence_penalty | number | Penalize tokens that have appeared at all so far. Positive values encourage new topics. |
response_format | one of | Constrain output to a JSON schema or an enum (structured outputs). |
seed | integer | Deterministic seed for sampling. Same seed + same prompt produces identical output. |
stop | array | Up to 4 sequences where the API will stop generating tokens. |
stream | boolean | Stream partial responses as Server-Sent Events. |
temperature | number | Sampling temperature; higher values produce more random output. 0 is deterministic. |
tool_choice | one of | Controls which (if any) tool is called: "none", "auto", "required", or a specific tool. |
tools | array | List of tools (functions) the model may call. |
top_p | number | Nucleus sampling: consider only tokens whose cumulative probability ≥ top_p. |
Standard OpenAI-compatible parameters. Consult the provider docs for model-specific behaviour.
Benchmark Scores
| Benchmark | Score |
|---|---|
| MMLU | 83% |
| SWE-bench Verified | 73.3% |
| GPQA Diamond | 63.2% |
Performance
160
tok / sec
output speed
Source: Anthropic docs + llm-stats.com, April 2026
Strengths & Limitations
Best For
Best-in-class cost efficiency
Fast inference speed
Computer use + extended thinking
Great for multi-agent pipelines
Limitations
Slightly weaker reasoning than Sonnet
No audio modality
Tags
FastCheapCodingAgentTool Use