Fast-mode variant of [Opus 5](/anthropic/claude-opus-5) - identical capabilities with higher output speed at 2x pricing relative to regular Opus 5. Learn more in Anthropic's docs: https://platform.claude.com/docs/en/build-with-claude/fast-…
Model details →Claude Opus 5 (Fast) vs OpenAI: o1
Claude Opus 5 (Fast) wins on 3 of 6 axes — pricing and capability skew in its favour for most workloads.
The latest and strongest model family from OpenAI, o1 is designed to spend more time thinking before responding. The o1 model series is trained with large-scale reinforcement learning to reason...
Model details →Side-by-side comparison
| Capability | Claude Opus 5 (Fast) | OpenAI: o1 | Winner |
|---|---|---|---|
| Context window Maximum number of input tokens the model can attend to in a single request. | 1M | 200K | 🏆 Claude Opus 5 (Fast) |
| Input price (per 1M) Cost per million input tokens billed by the provider. | $10.00 | $15.00 | 🏆 Claude Opus 5 (Fast) |
| Output price (per 1M) Cost per million output tokens billed by the provider. | $50.00 | $60.00 | 🏆 Claude Opus 5 (Fast) |
| Tool / function calling First-class support for emitting structured tool calls. | Yes | Yes | Tie |
| Vision input Accepts image inputs alongside text. | Yes | Yes | Tie |
| Reasoning mode Internal chain-of-thought / extended-thinking support. | Yes | Yes | Tie |
Frequently asked questions
Is Claude Opus 5 (Fast) better than OpenAI: o1?
Claude Opus 5 (Fast) wins on 3 of 6 axes — pricing and capability skew in its favour for most workloads.
What's the price difference between Claude Opus 5 (Fast) and OpenAI: o1?
Input: $10.00 vs $15.00 per 1M tokens. Output: $50.00 vs $60.00 per 1M tokens.
What context windows do Claude Opus 5 (Fast) and OpenAI: o1 support?
Claude Opus 5 (Fast) supports up to 1M tokens. OpenAI: o1 supports up to 200K tokens.
Do both Claude Opus 5 (Fast) and OpenAI: o1 support tool calling?
Claude Opus 5 (Fast): yes. OpenAI: o1: yes.
Compare Claude Opus 5 (Fast) with other models
vs Anthropic Claude Haiku Latestvs Anthropic Claude Sonnet Latestvs Anthropic: Claude Fable Latestvs Anthropic: Claude Opus Latest