Claude Opus 4.5 API — pricing & specs
Claude Opus 4.5 is Anthropic's most capable Claude tier, a text-only model for demanding reasoning, coding, and agentic workflows. As an earlier pinned-stable snapshot within the Opus 4 line, sitting below versions 4.6, 4.7, and 4.8, it suits reproducible deployments that need a fixed release. On KeepRouter, Claude Opus 4.5 costs $5 per 1M input tokens and $25 per 1M output tokens, billed at cost with no markup and no monthly fee. Call it through the OpenAI- or Anthropic-compatible API with the model id claude-opus-4-5.
| Maker | Anthropic |
|---|---|
| Modality | Text |
| Pricing | $5 per 1M input tokens and $25 per 1M output tokens |
Frequently asked questions
How much does Claude Opus 4.5 cost on KeepRouter?
Claude Opus 4.5 is $5 per 1M input tokens and $25 per 1M output tokens, billed at cost with no markup and no monthly fee.
Who makes Claude Opus 4.5?
Claude Opus 4.5 is made by Anthropic. KeepRouter provides it through one OpenAI- and Anthropic-compatible API.
How do I call Claude Opus 4.5 via API?
Point your OpenAI- or Anthropic-compatible client at KeepRouter and set the model to "claude-opus-4-5". No provider-specific SDK needed.