Frontier models

Claude Haiku 4.5

Fastest near-frontier model for cost-sensitive work and sub-agents.

Training

Reliable knowledge cutoff: February 2025. Training data cutoff: July 2025 (older than the Claude 5.x line). Parameter count, FLOPs, dataset mix, and any RLHF / RLVR / RLAIF recipe tied to this SKU: UNKNOWN.

Inference

Extended thinking (not adaptive). The effort parameter is not supported. Latency class is the fastest in the current Claude lineup.

Context

200K token context window. 64K max output tokens. Modalities: text and image in, text out; multilingual; vision; tool use.

Methods

Extended thinking plus tools. Exact train-time RL recipe at SKU level: UNKNOWN.

Benchmarking

UNKNOWN. No lab-published score table for Claude Haiku 4.5 appears in our sources. Do not invent scores.

Hardware

Anthropic trains and runs Claude on AWS Trainium, Google TPUs, and NVIDIA GPUs. Amazon is the primary cloud and training partner. More than 1 million Trainium2 chips in use as of April 2026. Per-SKU serving silicon: UNKNOWN. Buyers purchase API tokens, not a named Claude GPU SKU.