Claude Sonnet 5

Published

Jun 30, 2026

Claude Sonnet 5 is an AI model developed by Anthropic (United States), first published in June 2026. It works in the language and multimodal domain, on tasks such as language modeling/generation and question answering.

Epoch AI has no training-compute estimate for this model.

Access: API access. Its weights are not openly released. Epoch AI rates the confidence of this record as confident.

Full record

Organization: Anthropic
Country of organization: United States
Domain: Language, Multimodal
Task: Language modeling/generation, Question answering
Model accessibility: API access
Open weights: No
Epoch confidence: Confident

Benchmark results

01

Epoch Capabilities Index

ECI Score

153.5