Claude Sonnet 4
Balanced Claude model for coding, analysis, agent workflows, and cost control
ECI STANDING#99 of 266
SCORE141.69139.18–143.08 CI
FRONTIER LAGLaunched 5.1 months behindScores about what o1 did in December 2024.
SCORES LIKE THESE MODELSo1OpenAI · Dec 2024141.86
Full Epoch Capabilities Index ranking ↗Gemma 4 26B A4BGoogle DeepMind · Apr 2026141.86
Gemini 2.5 Flash (May 2025)Google DeepMind · May 2025141.54
DeepSeek-R1 (May 2025)DeepSeek · May 2025141.29
From the lab
Launch announcement · May 22, 2025Released Claude Opus 4 and Claude Sonnet 4RELEASE DATEMay 22, 2025
WEIGHTSClosed weights
CONTEXT WINDOW200K
MAX OUTPUT64K
REASONINGYes
TOOL CALLINGYes
INPUTStext, image, pdf
OUTPUTStext
Specifications from Models.dev. Availability and limits may differ by provider. Benchmark scores come from Epoch AI under CC BY 4.0.