Back to AnthropicModel FamilyClaude 4Developed by Anthropic. Explore the 2 variants available in this generation.Claude Opus 4AnthropicAnthropicAPI OnlyMay 2025LineageClaude 3 (Opus)|Claude 4.1 (Opus)Claude Sonnet 4AnthropicAnthropicAPI OnlyMay 2025LineageClaude 3.7 (Sonnet)|Claude 4.5 (Sonnet)