Claude Sonnet 4.5 (32k thinking)
ModelActiveby Anthropic · family “claude-sonnetk-thinking”
Epoch Capabilities Index
Not scored by Epoch AI
Released
29 Sep 2025
Context window
Unknown
Max output
Unknown
Input $ / 1M tokens
Unknown
Output $ / 1M tokens
Unknown
Cached input $ / 1M
Unknown
Each benchmark shown separately with its own source
Benchmark results (11)
| Benchmark | Domain | Score | vs best recorded | Setting | Run | Source |
|---|---|---|---|---|---|---|
| FrontierMath-Tiers-1-3-v2-Private | math | 23.9% ±2.5 | 25% | 32K | 11 Jun 2026 | Eval log ↗ |
| FrontierMath-Tier-4-v2-Private | math | 2.4% ±2.4 | 2% | 32K | 11 Jun 2026 | Eval log ↗ |
| Chess Puzzles | games | 12.0% ±3.3 | 17% | 32K | 8 Dec 2025 | Eval log ↗ |
| FrontierMath-Tier-4-2025-07-01-Privatesuperseded | math | 4.2% ±2.9 | 9% | 32K | 22 Oct 2025 | Epoch ↗ |
| ARC-AGI-2 | reasoning | 13.6% | 14% | 32K | — | External ↗ |
| FrontierMath-2025-02-28-Privatesuperseded | math | 15.2% ±2.1 | 29% | 32K | 16 Nov 2025 | Epoch ↗ |
| VPCT | multimodal | 39.8% | 44% | 32K | — | External ↗ |
| OTIS Mock AIME 2024-2025 | math | 77.8% ±6.3 | 78% | 32K | 21 Oct 2025 | Eval log ↗ |
| GPQA diamond | science | 81.7% ±2.8 | 85% | 32K | 21 Oct 2025 | Eval log ↗ |
| MATH level 5 | math | 97.7% ±0.4 | 100% | 32K | 21 Oct 2025 | Epoch ↗ |
| ARC-AGI | reasoning | 63.7% | 65% | 32K | — | External ↗ |
Source: Epoch AI Benchmarking Hub (CC BY 4.0). “External” rows are leaderboard results Epoch collects from third parties. Best reported setting per benchmark is shown.
API list price over time
Price history
$ per 1M tokens
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Events
- Model launchMajorAnthropic releases Claude Sonnet 4.5 (32k thinking)Epoch AI Benchmarking Hub