Claude Opus 4.5
Anthropic
Key facts · verified Oct 29, 2026
Claude Opus 4.5 is an Anthropic model. Its API price is $5 per million input tokens and $25 per million output tokens. Its context window is 200K tokens. It ranks #49 on LMArena's text leaderboard (Elo 1470, read 1 Nov 2026). Source: platform.claude.com.
Claude Opus 4.5 is a model from Anthropic. It is listed at $5 per million input tokens and $25 per million output, with a context window of 200K tokens. On LMArena's text leaderboard it scores 1470 Elo (rank 49). Its strongest category there is longer queries, at 24th, and its weakest is mathematics, at 65th. Figures here come from LMArena’s published dataset rather than from the vendor’s own documentation.
Pricing & specs checkedSource: vendor documentation · checked Oct 29, 2026LMArena: 1470 Elo (rank 49) · source · retrieved Nov 1, 2026
Full Specifications
$5 / $25 per million tokens | |
|---|---|
| Identity | |
| Developer | Anthropic |
| Licence | Proprietary |
| Self-hostable | No |
| Cost | |
| Blended $/1M tokensinput × 0.75 + output × 0.25 | $10.000 / 1M tokens |
| Input price | $5.000 / 1M tokens |
| Output price | $25.000 / 1M tokens |
| Capacity | |
| Context window | 200K tokens |
| Measured quality | |
| LMArena Elo | 1470 (checked Nov 2026) |
| LMArena rank | Rank 49 |
| Elo per dollarLMArena Elo ÷ blended $/1M tokens | 147 |