Claude Haiku 4.5vsClaude Sonnet 4

Claude Haiku 4.5 is Anthropic's fastest and most affordable model in the Claude family, designed for high-throughput applications where speed and cost-efficiency are paramount. Despite being the lightest model in the lineup, it delivers surprisingly strong performance on classification, extraction, summarization, and simple reasoning tasks. With a 200K context window and pricing at just $1.00 per million input tokens, it's ideal for processing large volumes of data quickly — from customer support triage to content moderation to data extraction. Haiku 4.5 responds in milliseconds, making it suitable for real-time applications where users expect instant responses. It's the go-to choice for builders who need Claude's safety and quality characteristics at scale.

Claude Sonnet 4 is Anthropic's balanced mid-tier model, offering an excellent combination of intelligence, speed, and cost-effectiveness. It ranks among the top 5 models globally on arena benchmarks while being significantly more affordable than Opus 4. With a 200K token context window, Sonnet 4 handles long documents and complex codebases with ease. The model excels at coding tasks (strong SWE-bench performance), long-form writing, document analysis, and structured data extraction. Its extended thinking capabilities allow it to tackle complex problems while maintaining fast response times for everyday tasks. Sonnet 4 is the most popular Claude model for production applications, offering the best price-to-performance ratio in Anthropic's lineup. It supports tool use, vision capabilities, and works seamlessly in agentic workflows.