Claude Sonnet 4.5
by Anthropic
· Claude 4 family · released Sep 29, 2025
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Released September 29, 2025 alongside Opus 4.5, Sonnet 4.5 matches much of Claude Opus 4.1's performance at a fifth of the cost, with a July 2025 knowledge cutoff and strong agentic coding.
Pricing
Launch price (from Sep 29, 2025)
$3.00 in / $15.00 out per 1M tokens
Current price (since Sep 29, 2025)
$3.00 in / $15.00 out per 1M tokens
| Tier | Effective | In $/M | Out $/M | Cache $/M | Per image | Per second | Source |
|---|---|---|---|---|---|---|---|
| Standard | Sep 29, 2025 – now | $3.00 | $15.00 | - | - | - | - |
Specifications
| Model type | Text LLM |
|---|---|
| Architecture | Unknown |
| Parameters | Not disclosed |
| Context window | 200K tokens |
| Max output | 64K tokens |
| Knowledge cutoff | Jul 31, 2025 |
| License | Proprietary |
| Modalities | Text input Image input Text output |
| Tags | Agentic Coding Reasoning Vision |
| End of life | Not disclosed |
| Last verified | Not disclosed |