Claude Sonnet 4.5 vs InternS1

Claude Sonnet 4.5

Anthropic

Claude Sonnet 4.5, released by Anthropic in September 2025, is a large language model from the Claude 4.5 family that balances response quality and efficiency for coding, agentic tasks, and analytical work. It features a 200K token context window (extendable to 1M tokens in beta), 64K maximum output tokens, native image understanding, and extended thinking support. Sonnet 4.5 targets use cases that require a balance of throughput and reasoning depth, including code generation, data analysis, and multi-step agentic pipelines.

Shanghai AI Lab

InternS1, released by Shanghai AI Laboratory at WAIC 2025 on July 26, 2025, is a multimodal scientific reasoning large language model designed for advanced problem-solving across mathematics, physics, chemistry, and related domains. It supports text, image, and potentially other scientific data formats as input, and demonstrated strong performance on competition-level scientific benchmarks. InternS1 targets open-source scientific research, STEM education, and applications requiring deep domain reasoning across natural science disciplines.