Claude Sonnet 4.5 is Anthropic’s most advanced Sonnet model to date, optimized for real-world agents and coding workflows. It delivers state-of-the-art performance on coding benchmarks such as SWE-bench Verified, with...
Anthropic: Claude Sonnet 4.5 — Anthropic. Context window 1,000,000 tokens. API pricing (per 1M tokens): Input $3, Output $15. License: Proprietary. LMArena 1,439. GPQA Diamond 73.7%.
| Provider | Anthropic |
|---|---|
| API model ID | anthropic/claude-sonnet-4.5 |
| Tier | Frontier |
| Context window | 1,000,000 tokens |
| Max output | 64,000 tokens |
| License | Proprietary |
| API pricing (per 1M tokens) · Input | $3 |
| API pricing (per 1M tokens) · Output | $15 |
| LMArena | 1,439 (claude-sonnet-4-5-20250929) |
| GPQA Diamond | 73.7% |
LMArena (CC-BY 4.0, best reasoning setting, 2026-10-02) · GPQA Diamond: Epoch AI (CC-BY 4.0)
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